Summer happens when the Earth is closest to the Sun.
True or False

!!!HELP QUICK!!!

Answers

Answer 1

Answer: False

Explanation:

Summer happens when the Earth is far away from the Sum

Answer 2
true, earth gets closer to the sun so it gets hot

Related Questions

Solar Energy Supply Part 4 0.0/5.0 puntos (calificado) Now let's look at the land needed for solar to supply all the energy needs of the USA. Since the electricity can be used with nearly 100% efficie

Answers

land needed for solar to supply all the energy needs of the USA is Energy production / 20 W/ft².

To determine the land needed for solar energy to supply all the energy needs of the USA, we need to consider the total energy consumption of the country and the efficiency of solar panels.

The energy consumption of the USA varies over time, but according to the U.S. Energy Information Administration (EIA), the total primary energy consumption in 2020 was approximately 92.94 quadrillion British thermal units (Btu).

To convert the energy consumption into the energy produced by solar panels, we need to consider the efficiency of solar panels. The efficiency of solar panels can vary, but let's assume an average efficiency of 20%. This means that solar panels can convert 20% of the sunlight they receive into usable electricity.

Now, we can calculate the energy production from solar panels:

Energy production = Energy consumption / Solar panel efficiency

Energy production = 92.94 quadrillion Btu / 20%

To convert the energy production into the area of land needed, we need to consider the average energy production per unit area of solar panels. The average energy production of solar panels can vary based on factors such as location, sunlight intensity, and panel technology. Let's assume an average energy production of 20 watts per square foot (W/ft²).

Now, we can calculate the land needed:

Land needed = Energy production / Average energy production per unit area

Land needed = Energy production / 20 W/ft²

The resulting value will be in square feet (ft²), representing the land area needed for solar panels to supply all the energy needs of the USA.

It's important to note that this calculation provides a general estimation based on the given assumptions of energy consumption, solar panel efficiency, and average energy production per unit area. The actual land needed may vary depending on specific factors and technological advancements in the future.

know more about solar energy click here:

https://brainly.com/question/9704099

#SPJ11

Why do hydrogen atoms form a molecule but helium atoms do not?

Answers

Answer:

Explanation:

In terms of old school electron shells - One Hydrogen atom on it's own has an empty shell, and therefore to fill the shell it needs another electron. In the case of Helium, it already has two electrons at the same energy level - so it cannot accept any new electrons i.e. it cannot form new bonds.

Answer:

Hydrogen atoms can form a molecule as 2 hydrogen atoms together can result in a low energy combination of 2 electrons of the same energy level.

Explanation: Helium atoms already have 2 electrons of the same energy so therefore it cannot accept more.

______and____ are early tetrapods that do not have features unique to fish. Describe how these two species differ antaomically and what that means about where they each live.

Answers

What he said! Wow good

Innate immunity and acquired immunity are both _____. See Concept 43.1 (Page 953) View Available Hint(s) Innate immunity and acquired immunity are both _____. See Concept 43.1 (Page 953) dependent on surface secretions from sebaceous and sweat glands, which give the skin an acidic pH that is unfavorable for bacterial colonization based on the trapping of microbes by mucus dependent exclusively on cell-mediated responses characteristics of all vertebrate animals dependent on tears, saliva, and mucous secretions that contain lysozyme, an enzyme that digests bacterial cell walls

Answers

Answer:

The correct answer is - characteristics of all vertebrate animals.

Explanation:

Innate immunity is the first line of the immune system that comes with birth whereas adaptive or acquired immunity is the immunity that comes throughout life by experiencing or developing the immune system. Adaptive or acquired immunity is the immune response that comes through cell-mediated responses whereas innate immunity is the immune response that includes sweat glands and secretion from the skin. innate immune responses also include digesting and killing bacteria by the saliva, enzymes, lysozymes.

The only characteristic among these that present in both is that they both immune systems found in all vertebrates.

Implantation Which of the following sequences correctly describes prenatal development? A. blastocyst implants in uterus, zygote forms, heart begins beating, lungs can breathe air, sex organs become visible B. blastocyst implants in the uterus, zygote forms, heart begins beating, sex organs become visible, lungs can breathe air C. zygote forms, blastocyst implants in the uterus, heart begins beating, sex organs become visible, lungs can breathe air D. zygote forms, blastocyst implants in the uterus, sex organs become visible, heart begins beating, lungs can breathe air 3. Which of the following correrti​

Answers

Explanation:

A because in the pental development the men and women sex others for there fun and baby in this ara

True or False? All mutations have a negative effect on a population of organisms.

Answers

Answer:

False, I believe. Mutations sometimes might have an effect that helps the population. Example: I've heard of Two-Headed snakes, and even seen some on the internet. They live their lives just fine, so I suppose the mutation was actually quite helpful.

Answer:

false

Explanation:

How is RNA different from DNA?
A. DNA is double stranded, contains uracil, sugar is ribose

B. DNA is single stranded , contains thymine , sugar is deoxyribose

C. RNA is single stranded, contains thymine , sugar is ribose.

D. RNA is single stranded , contains uracil , sugar is ribose

Answers

Answer:

D. RNA is single stranded , contains uracil, sugar is ribose

Answer:

D. RNA is single stranded , contains uracil , sugar is ribose

Explanation:

RNA contains the sugar ribose, while DNA contains the slightly different sugar deoxyribose

Some evidence that vaccines are effective.

Answers

Answer:

Vaccines prevent diseases, its just proven. Most Anti Vaccers end up getting Measles, etc. But people with vaccines usually dont.

Explanation:

we are living proof to be honest, i got the chicken pox vaccine and never had it once in my life. Same thing with many other diseases we get vaccinated for.    

what is the relationship between abrasion and the hardness of a rock mineral?

Answers

Answer:

Hardness (H) is the resistance of a mineral to scratching. The degree of hardness is determined by observing the comparative ease or difficulty with which one mineral is scratched by another or by a steel tool.

Explanation:

https://www.britannica.com/science/mineral-chemical-compound/Hardness Hope this helps

Roan cattle are heterozygous hybrids of a cross between a white bull (WW) and a red cow (RR).
If a roan bull were crossed with a red cow, what would be the possible phenotypes of thelr offspring?
a
1 Red; 2 White: 1 Roan
b
O Red: 2 White: 2 Roan
c с
2 Red: 0 White; 1 Roan
d
2 Red: 0 White; 2 Roan

Answers

The answer is D
2 red and 2 roan

Brain lateralization refers to the ability of the brain to process multisensory information ability of the brain to process multisensory information A capacity of the brain to control basic motor movements capacity of the brain to control basic motor movements B aptitude of the brain to produce speech aptitude of the brain to produce speech C ability of the brain to control basic functions such as respiration and blood circulation ability of the brain to control basic functions such as respiration and blood circulation D inclination for certain cognitive processes to be specialized to one hemis

Answers

Answer:

The correct answer is D ''inclination for certain cognitive processes to be specialized to one hemisphere of the brain or the other.'

Explanation:

Lateralization refers to the different specialization of the cerebral hemispheres, that is, it is the functional specialization of the nervous system that is observed to a different degree on one side or the other of the neuroaxis. Our brain is subdivided into two hemispheres, the right and the left. The left hemisphere is more specialized in language and control of emotions and the right in spatial thinking, perception of emotions and facial recognition.

What types of light can plant cells absorb? Select 3 answers to get this correct.

Answers

It will be 1,2,4

You can’t see x-rays with machine

The overriding problem with both theories of muscle growth, hypertrophy and hyperplasia, is that __________. A. neither can be accepted as correct because muscles growth is difficult to study in humans B. neither one is theoretically possible C. neither has been studied by reputable scientists D. neither has been accepted by member of the fitness community Please select the best answer from the choices provided.

Answers

Answer: A. neither can be accepted as correct because muscles growth is difficult to study in humans.

Explanation:

Hypertrophy can be defined as the increase in the fiber size of the muscle whereas the hyperplasia can be defined as the increase in the number of muscle fibers. Additionally the hypertrophy suggests that adding more proteins to the fibers is suggestive of the growth of the muscles. But these two theories cannot be directly related to the muscle growth in humans as the development and growth of muscles are dependent upon several factors like diet, any kind of disease which restrict the muscle growth and movement, physical activities, mineral availability responsible for growth, malnutrition, and others.

Answer:

A

Explanation:

The level of carbon dioxide in the blood is monitored by nerve tissue. If you exercise strenuously, the increase in cellular respiration consumes oxygen from the blood and produces surplus carbon dioxide removed in the blood. Since this physical exertion requires faster breathing to replenish oxygen supplies and carry away carbon dioxide, the carbon dioxide sensors result in signals from the brain to increase breathing rate. After you have rested, and carbon dioxide levels are back to normal, your breathing rate decreases too. This is an example of

Answers

Answer:

Negative feedback.

Explanation:

The normal carbon dioxide levels after resting, the breathing rate also decreases which is an example of negative feedback because the body moves towards stability or equilibrium conditions. There is a direct relationship between breathing rate and carbondioxide levels means if one is increases the other automatically increases in order to maintain homeostasis in the body so we can say that this relationship is very important to maintain .stability in the body

In an effort to control his blood glucose levels, jose is counting grams of which macronutrient?

Answers

To control his blood glucose levels, Jose is likely counting grams of carbohydrates.

Carbohydrates are one of the three macronutrients, along with proteins and fats. Carbohydrates have the most significant impact on blood glucose levels as they are broken down into sugar (glucose) during digestion. When carbohydrates are consumed, they are converted into glucose, which is then absorbed into the bloodstream, leading to an increase in blood glucose levels.

By counting grams of carbohydrates, Jose can monitor and regulate his carbohydrate intake to manage his blood glucose levels. This can be particularly important for individuals with conditions such as diabetes, where controlling blood sugar levels is crucial for maintaining overall health and managing the condition effectively.

It's worth noting that other macronutrients, such as proteins and fats, also play a role in overall nutrition and may have an impact on blood glucose levels to a lesser extent. However, carbohydrates have the most significant and direct influence on blood glucose, making them the primary macronutrient of focus when it comes to blood glucose control.

Here you can learn more about blood glucose levels

https://brainly.com/question/4200474#

#SPJ11  

Newyork is near 40 degrees N. What general direction is air moving in Newyork

Answers

Answer:

The air in New York moves to the north.  

Explanation:

At a global level, it occurs unequal warming of the atmosphere, which depends on many factors and varies with latitude. These temperature differences occur because solar radiation reaches the earth differently at different latitudes degrees. The result is the formation of convective cells of atmospheric air circulation: Hardley cell, Ferrel cell, and Polar cell.    

The term convective cell refers to air getting warm, expanding, getting less dense, and ascending. During ascension, it gets colder because of the change in high, contracting, becoming thicker. Finally, it descends.

In each hemisphere, warm air ascends at the equator and approximately at 60º latitude. Cold air descends at approximately 30º latitude and the poles. These air masses circulation generates superficial winds that blow toward the equator between 0º-30º, and toward the poles between 30º-60º lat.  

Ferrel cell occurs between 30º and 60º latitude. At 30º lat, the cold air coming from the north in the tropopause meets the cold air coming from 0º, and both descend to lower altitudes due to its density and low temperature. When these air masses reach the ground, they diverge.  One part goes to 0º lat, while the other part goes forward to the north.  As it moves north, it gets warmer for being at lower altitudes. At 60º, this warm air coming from the 30º meets the polar air coming from 90º, and as it is warmer it ascends again. When it ascends to the tropopause, it is pushed by new air and moves to the south again. While doing so, it loses heat and becomes denser, descending again at 30º.  And so the cycle starts all over again. New York is located at 40º latitude approximately, so air goes forward to the north pole near the ground, but at 60º it elevates again. New York is then affected by the Ferrel cell.        

In the attached image you will find the three cells, circulating in different directions.  

can someone please answer this for me?​

Answers

Answer:

50 %

Explanation:

Using a punnets square the four possible crosses are Hh, Hh, hh, and hh. This means there is a 50% chance the child has hh or hemophilia

What type of cells are body cells

Answers

Answer:

there are 4 type of body cell

Select the correct image.
Which image best illustrates the magma convection currents within Earth’s interior?

Answers

Answer:

the thrid one is the best one

The image that best illustrates the magma convection currents within Earth’s interior is the bottom left.

What is Convection?

Convection may be defined as a process through which the transfer of heat due to the bulk movement of molecules within a fluid takes place. The current which is produced by the movement of these molecules is known as the Convection current.

Convection currents are present in the mantle region of the earth's surface. In the process of heating, magma rises from deep inside the mantle and then cooled the mantle as it flows down. This cyclic movement of magma constructs convection current within the region of the earth's interiors.

Therefore, the image that best illustrates the magma convection currents within Earth’s interior is the bottom left.

To learn more about Convection currents, refer to the link:

https://brainly.com/question/20295382

#SPJ2

explain how carbon atoms can move to co2 in the air into an organic molecule inside a plant and then back to co2 in the air

Answers

Answer:

Your carbon atom enters the leaf as CO2 (carbon dioxide) from the atmosphere. In the leaf, chlorophyll uses the energy from the sun to convert CO2 and H2O to the sugar glucose, C6H12O6. Your carbon atom is part of this molecule; it is now one of the carbons in the glucose.

Next, the glucose carrying your carbon atom is sent down the phloem tissue of the carrot plant to the root, which is the carrot itself. Enzymes in the carrot root connect the glucose molecule with your carbon atom into a chain with other glucose molecules, forming cellulose, or plant starch, and there you go. Your carbon atom went from being part of an atmospheric gas to a starch via photosynthesis and starch formation in the root.

Explanation:

(f) would you recommend using the model found in part (a) to predict the bone mineral density of a woman who consumes two cans of cola per day? why?

Answers

The model found in part (a) can not be used to predict the bone mineral density of a woman who consumes two cans of cola per day. To write the least-squares regression equation, and then use this equation to predict the bone mineral density for a woman weighing 68 kg.

Firstly, it is noteworthy that the predictor variable in the given regression model is "weight (kg)". In other words, the model is built on the association between the weight of women and their bone mineral density. Therefore, the independent variable in the regression model is "weight", not "consumption of cola".You can not use this model to predict the bone mineral density of a woman who consumes two cans of cola per day because the regression model does not involve the variable "consumption of cola". Since the given regression equation is solely built on the association between weight and bone mineral density, using this model to predict bone mineral density for a woman who consumes two cans of cola per day would lead to unreliable results.

for further information on women visit:

https://brainly.com/question/928992

#SPJ11

During summer in the Northern Hemisphere,


A. the Sun rises in the Southeast and sets in the Southwest.

B. the Sun appears lower in the sky than during other seasons.

C. there are fewer hours of visible sunlight each day than during other seasons.

D. the Sun rises earlier and sets later than during other seasons.

Answers

Answer:

B the sun appears lower in the sky

What effects will be manifest in an extremely small population with little to no migration?

Answers

An extremely small population with little to no migration can have several effects.

These effects include an increased risk of genetic drift and inbreeding depression.

Genetic drift: Genetic drift is a random change in allele frequencies that occurs in small populations. Since smaller populations have less genetic variation, genetic drift is more common. Genetic drift can reduce genetic diversity in a population, which can lead to the fixation of deleterious alleles.

Inbreeding depression: Inbreeding depression is a loss of fitness that occurs when closely related individuals mate and produce offspring. Inbreeding depression can occur when a population becomes small and isolated, and the mating pool is reduced. Inbreeding depression can lead to reduced fertility, increased susceptibility to disease, and lower survival rates.

Additionally, inbreeding depression can reduce genetic diversity in a population, which can make it more susceptible to environmental change. Therefore, an extremely small population with little to no migration can lead to an increased risk of genetic drift and inbreeding depression.

If you need to learn more about the population click here:

https://brainly.com/question/29885712

#SPJ11

Explain the difference between herbivores, carnivores and omnivores​

Answers

Answer:

Herbivores are organisms that eat plants only. Carnivores are organisms that eat other animals only (meat). Whereas, omnivores are organisms that eat both plants and animals.  

hope this helps and is right. p.s. i really need brainliest :)

Animals that eat plants exclusively are herbivores, and animals that eat only meat are carnivores. When animals eat both plants and meat, they are called omnivores. ... These carnivores may eat insects and worms. Carnivorous animals have strong jaws and sharp teeth to enable them to tear and rip prey.

The regulation of body temperature is a contributor to homeostasis. What body
system is responsible for this?
Digestive System
Musculoskeletal System
Nervous System
Circulatory System

Answers

Answer:

its the nervous system and the endocrine system

Explanation:

the nervous and the endocrine are the bodys main regulators

Saxitoxin is a paralytic shellfish poison. It inhibits permeability of sodium ions by acting as an antagonist at the receptor site. Predict the effects of saxitoxin?
A :
inhibits release of ACh
B :
increases muscle action potentials
C :
blocks muscle action potentials
D :
increases release of ACh

Answers

As saxitoxin inhibits the permeability of sodium ions by acting as antagonists, it will block the muscle action potential. Thus, the correct option is C.

Upon arrival of nerve impulse, acetylcholine is released from the synaptic end bulbs into the synaptic cleft. When acetylcholine binds to the receptor, it causes opening of ion channel which causes the inward movement of sodium ions into the muscle fibre. This triggers a muscle action potential.

Thus, if sodium ions are inhibited from flowing inwards by saxitonin, the muscle action potential will not occur.

Thu, the correct option is C.

Learn more about saxitoxin in:

https://brainly.com/question/15866689

#SPJ4

What do you think of when you hear the word "energy?"
I
(Pls somebody answer)

Answers

What comes up to my mind is a baby since they have the energy to stay up late and also cry a lot and loud

A researcher using random assignment:
a
puts half the group in the dependent variable group and half in the independent variable group in a random way.
b
places participants in the sample group or the population group randomly.
c
assigns participants to the experimental and control groups by chance.
d
gives half the sample the dependent variable and doesn't give anything to the other half.

Answers

AAnswer:A

Explanation:because why not

how was science relevant to the world​

Answers

Answer:

Science helped create almost everything today, medicinces,drought resistant food, technology, further education in doctoring, electricity etc.  

Explanation:

Which statement is accurate about natural selection?(1 point) A. Natural selection cannot inactivate genes. B. Natural selection does not impact reproduction rates. C. Natural selection does not change the alleles an organism has. D. Natural selection cannot occur through mutations.

Answers

Answer:

B

Explanation:

The correct option is "B" Natural selection does not impact reproduction rates according to the theory of Natural selection.

What are the factors of natural selection?

Natural selection is the process through which populations of living organisms adapt and change. There are four factors are required for natural selection are reproduction, heredity, variation in fitness or organisms, variation in individual characters among members of the population.

Hence, the option is "B" Natural selection does not impact reproduction rates according to the theory of Natural selection.

To learn more about Natural selection Click here:

https://brainly.com/question/2725702

Other Questions
qualitative research procedures are classified as either descriptive or causal t/f A Line Has Vector Equation = (0,-5,2)+S(1,1,-2), S R And Lies On A Plane . The Point P(2,-3,0) Also Lies On The Plane . Determine The Cartesian Equation Of This plane. Imagine we live in a Modigliani and Miller Proposition 1 world. By issuing debt and retiring common stock, which of the following risks will be amplified? a. Operating Risk b. Financial RIsk c. Both Operating and Financial Risk d. None of the above compute the work done by the force f = 2x2y, xz, 2z in moving an object along the parametrized curve r(t) = t, t2, t3 with 0 t 1 when force is measured in newtons and distance in meters19/10 Give the structures of the substitution products expected when 1-bromohexane reacts with:1.NaOCH2CH3 An economy operating on its long-run aggregate supply curve willA. achieve zero unemploymentB. see high inflationC. increase capacity if the price level decreasesD. have no cyclical unemploymentE. be in a recessionary output gap Kansas Enterprises purchased equipment for $80,500 on January 1, 2021. The equipment is expected to have a ten-year service life, with a residual value of $6,750 at the end of ten years. Using the double-declining balance method, depreciation expense for 2021 would be: (Do not round your intermediate calculations) Question 5 of 6 < > View Policies Current Attempt in Progress Bramble Corporation has retained earnings of $697,600 at January 1, 2020. Net income during 2020 was $1.692.900, and cash dividends declared and paid during 2020 totaled $81,700. Prepare a retained earnings statement for the year ended December 31, 2020. Assume an error was discovered: land costing $88,590 (net of tax) was charged to maintenance and repairs expense in 2019. (List items that increase retained earnings first.) BRAMBLE CORPORATION Retained Earnings Statement 4 -/1 E : I ddodia BRAMBLE CORPORATION Retained Earnings Statement # # 4 $ New Daniel Fox owned Fox & Lamberth Enterprises, Inc., a kitchen and bath remodeling business, in Dayton, Ohio. Fox leased a building from Carl and Bellulah Hussong. Craftsmen Home Improvement, Inc., also remodeled baths and kitchens. When Fox planned to close his business, Craftsmen expressed an interest in buying his showroom assets. Fox set a price of $50,000. Craftsmen's owners agreed and gave Fox a list of the desired items and "A Bill of Sale" that set the terms for payment. The parties did not discuss Fox's arrangement with the Hussongs, but Craftsmen expected to negotiate a new lease and extensively modified the premises, including removing some of the displays to its own showroom. When the Hussongs and Craftsmen could not agree on new terms, Craftsmen told Fox that the deal was off. Fox sued Craftsmen in state court for breach of contract. Craftsmen raised the Statute of Frauds as a defense. Craftsmen also claimed that the predominant factor of its agreement with Fox was a lease for the Hussongs' building. How should the court resolve this dispute? balance sheets prepared under ifrs and u.s. gaap show more similarities than differences.a. trueb. false A promissory note: Multiple Choice Is a. a short-term investment for the maker. b. Is a written promise to pay a specified amount of money at a certain date. c. Is a liability to the payee. d. Is another name for an installment receivable. which has greater capacity? missippi or a small mountain stream A $1,000 bond has a coupon of 9 percent and matures after ten years. Assume that the bond pays interest annually. a. What would be the bond's price if comparable debt yields 10 percent? Use Appendix B and Appendix D to answer the question. Round your answer to the nearest dollar. $ b. What would be the price if comparable debt yields 10 percent and the bond matures after five years? Use Appendix B and Appendix D to answer the question. Round your answer to the nearest dollar. $ c. Why are the prices different in a and b? The price of the bond in a is select than the price of the bond in b as the principal payment of the bond in a is-Select- v than the principal payment of the bond in b (in time). d. What are the current yields and the yields to maturity in a and b? Round your answers to two decimal places. The bond matures after ten years: % CY: YTM: % The bond matures after five years: % CY: YTM: % The table below shows the cost of a fixed basket of goods that a typical urban consumer would buy in the economy of Kindleberger, where the base period for the consumer price index (CPI) is the year 2000. The year for which you are determing the CPI is considered the current year. Please specify your answers to two decimal placesYear Cost of a basket of goods2000 $8,150.002011 $6,500.002012 $4,725.001. What is the CPI for 2000?2.What is the CPI for 2011?3.What is the CPI for 2012? Abigail, Bernard, Cornwallis, and Douglas each derive a distinct amount of utility from consuming apples and bananas. Initially, apples cost $2, bananas cost $1, and each person receives a weekly allowance of $20 to spend. For each of the four sets of preferences described below, calculate the compensating variation if the price of apples rises to $5. (a) (4) Abigail: U(a, b) = a + 2b (b) (4) Bernard: U(a, b) = 2a + b (c) (4) Cornwallis: U(a, b) = b-a (d) (4) Douglas: U(a, b) = min(a, 3b) Question 5 (28 points) Demand for Rover dogwalking services in Harrisonburg is given by the following inverse demand function: Pa(q) = 30- 10 Assume a population on an island grows intrinsically according to exponential growth with a rate of 0.11, but the population also experiences immigration from other islands. If the population increased from 103 to 18737 individuals in 14 years. What is the immigration rate in individuals per year? Round your answer to two decimal places, i.e. 5.45? Best advanced courses to learn in upcoming technology generation Solve the following system from Example 3 by the Gauss-Jordan method, and show the similarities in both methods by writing the equations next to the matrices.x+3y=7, 3x+4y=11 Chapter 2 lists four ways that you can help to protect your client's or your employer's trademark. One is to use the trademark symbol. Which one of the following methods is also listed in the chapter?a. Distinguish trademarks from other material, perhaps by setting the trademark in a different typeface or by using boldface type for emphasis.b. Use the trademarked item in various grammatical forms, including as an adjective (Xerox copiers), a noun (Xeroxes), and a verb (Xerox 500 copies).c. Use the plural form (Xeroxes) or the possessive form (Xerox's quality) of the term whenever possible.d. Consistently use one of the trademark symbols ( or ) in references to other trademarked items, whether or not your client or employer owns those trademarks.e. Include a prominent warning about the civil and criminal penalties for infringing on the protections afforded by trademark law, similar to the FBI warning about copyright that appears at the beginning of rental movies. explain why a 2 x 2 matrix can have at most two distinct eigenvalues. explain why an n x n matrix can have at most n distinct eigenvalues