A rock outcrop was found to have 78.88% of its parent u-238 isotope remaining. approximate the age of the outcrop. the half-life of u-238 is 4.5 billion years old.

Answers

Answer 1

Answer:

Answer:1.5*10^9 years

Step-by-step explanation:

The half life of the substance is given i.e 4.5B years. You can change it into seconds by multiplying it with 365 and 86400.

The current no of particles is given 78.88% which will be equal to 78.88 if you assume the substance had 100 no of particle initially.

Determine the decay constant by dividing 0.69 by half life

use these values in the equation for the answer.

[ln and e are inverse functions to eachother]


Related Questions

Pauley graphs the change in temperature of a glass of hot tea over time. he sees that the function appears to decrease quickly at first, then decrease more slowly as time passes. which best describes this function?

Answers

Non-linear graph best describes this function.

Why nonlinear?

As described in the question, Pauley graphs the change in temperature of a glass of hot tea over time. He sees that the function appears to decrease quickly at first, then decrease more slowly as time passes. It is linear because the graph decreases over time. It is linear because there is both an independent and a dependent variable but it doesn't satisfies one condition of being linear. Thus, It's Nonlinear because linear functions are increasing functions. It is nonlinear because linear functions increase or decrease at the same rate.

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Answer:

B

Step-by-step explanation:

The steps to derive the quadratic formula are shown below:

Step 1 ax2 + bx + c = 0
Step 2 ax2 + bx = − c
Step 3 x2 + b over a times x equals negative c over a
Step 4 x2 + b over a times x plus b squared over 4 times a squared equals negative c over a plus b squared over 4 times a squared
Step 5 x2 + b over a times x plus b squared over 4 times a squared equals negative 4 multiplied by a multiplied by c, all over 4 multiplied by a squared plus b squared over 4 times a squared
Step 6


Provide the next step to derive the quadratic formula. (1 point)

x plus b over 2 times a equals plus or minus b squared minus 4 times a times c all over the square root of 4 times a squared

x plus b over 2 times a equals plus or minus b minus 2 times a times c all over square root of 2 times a

x plus b over 2 times a equals plus or minus the square root of the quantity b squared minus 4 times a times c all over the square root of 4 times a squared

x plus b over 2 times a equals plus or minus the square root of the quantity b squared minus 4 times a times c all over the square root of 2 times a

Answers

Answer: [tex]x+\frac{b}{2a}=\pm \frac{\sqrt{b^2 - 4ac}}{\sqrt{4a^2}}[/tex]

Step-by-step explanation:

We can rewrite the left hand side as a perfect square, more specifically

[tex]\left(x+\frac{b}{2a} \right)^2[/tex]

So, taking the square root of both sides,

[tex]x+\frac{b}{2a}=\pm \frac{\sqrt{b^2 - 4ac}}{\sqrt{4a^2}}[/tex]

Compared to continental crust, oceanic crust is:
A. mostly granite
B. more dense
C. All of these
D. thicker

Answers

Answer:

B. more dense

The mean annual income of certified welders is normally distributed with a mean of $50,000 and a population standard deviation of $2,000. The ship building association wishes to find out whether their welders earn more or less than $50,000 annually. The alternate hypothesis is that the mean is not $50,000. If the level of significance is 0.10, what is the decision rule

Answers

Using the p-value method, the decision rule is:

|z| < 1.645: do not reject the null hypothesis.|z| > 1.645: reject the null hypothesis.

What is the relation between the p-value and the test hypothesis?

Depends on if the p-value is less or more than the significance level:

If it is more, the null hypothesis is not rejected.If it is less, it is rejected.

In this problem, we have a two-tailed test, as we are testing if the mean is different of a value. For a significance level of 0.1, the critical value of z(when a p-value of 0.1 is obtained) is of |z| = 1.645, hence the decision rule is:

|z| < 1.645: do not reject the null hypothesis.|z| > 1.645: reject the null hypothesis.

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I need help with this math question

Answers

Answer:

D = 12

Step-by-step explanation:

Side ST is corresponding to side QT. 9" / 3" = 3

3 is the proportion between the two triangles.

Side PT is the corresponding side to side RT.

PT = 4" x 3 = 12"

5 quick algebra 1 questions for 50 points!


Only answer if you know the answer, shout-out to subtomex0, tysm for the help!

Answers

Q 3 - c -

[tex]x {}^{2} - 8x - 9 = 0 \\ x + y = 8 \\ xy = - 9[/tex]

Two numbers who sum up to 8 and multiply to -9 are: 9 and -1

Q 4 - d -

[tex]g(x) = x {}^{2} - 7x + 12 \\ g(6) = 36 - 42 + 12 = 6 \\ g( - 7) = 49 + 49 + 12 = 110 \\ g( - 3) = 9 + 21 + 12 = 42 \\ g(4) = 16 - 28 + 12 = 0[/tex]

x=4 is a root

These problems can be approached in many ways: completing the square/factoring/using the quadratic formula...

Q 1 - c -h(x)= -2x+10h(0)=10 ( 0 , 10 )h(x)=0x=5 ( 5 , 0 )

Q 5 - True -f(x) = 2x²+3x-2f(x)=02x²+3x+2=0x=-2 x=1/2

Q 4 - 3 is the zero -

b

Answer:

Question 1:The correct answer is C. -1 and 9

Question 2: The correct answer is D.4

Question 3: The correct answer is C. The x-intercept of (5,0) and y-intercept of (0,10)

Question 4: The correct answer is B. True

Question 5: The correct answer is b.

In which year did Eugene, Oregon have the greatest difference between high and low temperatures in November?

A)November 2009
B)November 2010
C)November 2011
D)November 2008

Answers

I believe the answer is A) November 2009

What is the length of the hypotenuse of right ΔDEF shown? A) √5041 B) √2545 C) √497 D) √1063

Answers

The length of the hypotenuse of right triangle ΔDEF is 50.44 units

How to find hypotenuse of a right triangle?

The hypotenuse side can be found using Pythagoras theorem,

Therefore,

c² = a² + b²

where

c = hypotenusea and b are the other legs.

Therefore,

x² = 39² + 32²

x² = 1521 + 1024

x = √2545

x = 50.4479930225

x = 50.44

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Eight years ago, Marilyn invested $1000 in a stock. The table shows the
value of the stock over time.
Year
0
1
2
3
4
5
6
7
8
Value
$1000
$1095
$1200
$1314
$1440
$1580
$1730
$1890
$2070
Which is closest to the rate of change modeled by the function?
Leaming Inc.
Helo 13

Answers

Answer: 1.095

Step-by-step explanation:

The function is increasing, so the rate of change must be greater than 1.

A company earns a profit of $100 the first month it is in business. Every month after that, the company earns a profit that is 1.5 times the previous month's profit. What will the company's profit be in the fith month?

Answers

The company's profit in fifth month will be $506.25

Profit : The gain in an expenditure, that is when the return is higher than the original amount, then the gained extra amount is called profit.

Example : If someone sell a toy of $10 in $15, then he gained profit & his profit is $(15-10) = $5.

A company earns a profit of $100 the first month it is in business.

Every month after that, the company earns a profit that is 1.5 times the previous month's profit.

In 1st Month,

Profit = $100

In 2nd Month,

Profit = 1.5 times of profit of 1st month

         = 1.5 × $100

         = $150

In 3rd Month,

Profit = 1.5 times of the profit of 2nd month

         = 1.5 × $150

         = $225

In 4th Month,

Profit = 1.5 times of the profit of 3rd month

         = 1.5 × $225

         = $337.5

In 5th Month,

Profit = 1.5 times of the profit of 4th month

         = 1.5 × $337.5

         = $506.25

So, the profit of 5th month = $506.25

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In a large population, 76% of the households have cable tv. A simple random sample of 225 households is to be contacted and the sample proportion computed. What is the mean and standard deviation of the sampling distribution of the sample proportions

Answers

0.017559

It is given that:

Probability of Households Having cable TV, p₀ = 76% = 0.76

Therefore,

The probability that the Households not having cable TV = 1 - 0.76 = 0.24

Sample size, n = 225 households

sample proportions is less than 82% i.e p = 0.82

Now,

The standard error, SE = [tex]\sqrt{} \frac{0.76(1-0.76)}{225}[/tex]

= 0.02847

Z = [tex]\frac{0.82-0.76}{0.02847}[/tex]

Z = 2.107

therefore, P(sample porportions < 0.82) = P(Z < 2.107)

now from the p value from the Z table we get P(sample porportions < 0.82) =  0.017559

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Given the following linear function sketch the graph of the function and find the domain and range. f( x ) = 2/7 x− 2

Answers

Answer:

Domain: All Real Numbers Range: All Real Numbers

Step-by-step explanation:

The domain and range is going to be infinite. The linear function will be using the x and y- axis in order to continue being a function. The y-intercept will be -2 on the y-axis. I recommend using the rise-over-run method for your slope value. from the point (0, -2) on the y-axis. Go up two on the y-axis, and right 7 on the x-axis.

Sorry, it may be difficult to explain through words.

Classify the polynomial by its degree and number of terms. Select all choices that apply for each polynomial.
(which is correct ??)

Answers

Step-by-step explanation:

The polynomial highest degree is 2 so the degree is 2.

The binomial have three terms so it is a trinomial.

An architect's sketch of plans for the front of a garage in the shape of pentagon is shown below. What is the approximate perimeter of the
front of the garage?
-8
-6 -4 -2
A. about 36 ft
B. about 21 ft
C. about 10 ft
D. about 77 ft

Answers

Using it's concept, it is found that the approximate perimeter of the front of the garage is:

A. about 36 ft.

What is the perimeter of a figure?

The perimeter of a figure is given by the total length of it's boundary.

In this problem, we have that:

The bottom boundary has length of 10 units.The two lateral boundaries have lengths of 7 units.There are two top boundaries, which are the hypotenuses of a right triangle with legs 3 and 5, hence:

[tex]t = \sqrt{3^2 + 5^2} = 5.83[/tex]

Hence the perimeter of the figure is:

P = 10 + 2 x 7 + 2 x 5.83 = 35.66.

Rounding, it is of about 36 ft, hence option A is correct.

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I need answer fast!!
3. Write the rule that describes the second transformation. (5 points)

Answers

The rule that describes the second transformation is; Rotated at 90° clockwise

How to Interpret Transformations?

From the given diagram we can see that;

The transformation from Rectangle ABCD to A'B'C'D' follows the transformation sequence of;

Shift 1 unit downwards then translate 5 units to the right.

However, for the transformation of A'B'C'D' to A"B"C"D", we see that the transformation is; Rotated at 90° clockwise

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John lives in Vermont and Julie lives in Florida. One January day, it was 52°F in Florida and 9°F in Vermont. What was the difference in temperature.

Answers

Answer:

43

Step-by-step explanation:

52-9=43

Find the length of the midsegment .
A.15
B.44
C.22
D.13

Answers

Answer: 22

Step-by-step explanation:

Using the triangle midsegment theorem,

[tex]2(5x+2)=3x+32\\\\10x+4=3x+32\\\\7x+4=32\\\\7x=28\\\\x=4[/tex]

So, the length of the midsegment is 5(4) + 2 = 22

The weight of an apple is 150g, rounded to the nearest 5g. what is the lower bound and upper bound?

Answers

The lower bound is 147.5 and the upper bound is 152.5.

Given the weight of an apple 150 g rounded to the nearest 5g.

We have to find lower bound and upper bound.

Lower bound is an element less than or equal to all the elements in a given set.

Upper bound is an element greater than all the elements in a given set.

Lower bound= Number 1- (Number nearest to  which number 1 is rounded)/2

Upper bound=Number 1+(number nearest to which number 1 is rounded)/2

Weight of an apple =150 g

Lower bound=150-5/2

=150-2.5

=147.5

Upper bound=150+5/2

=150+2.5

=152.5

Hence the lower bound is 147.5 and upper bound is 152.5.

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A tire on a car has an outside diameter of 36.30 in. Through what angle​ (in radians) does the tire turn while traveling 1 ​mile?

Answers

Answer: 3491.91 radians

Step-by-step explanation:

The total distance in inches traveled by car = 63,360 inches (1 mile)

Total Revolution made by tire through traveling =

[tex]=\frac{63360}{\pi *36.30}[/tex]

We know 1 revolution angle made by tire = 2π radian (360 degrees/1 revolution of unit circle)

In   [tex]\frac{63360}{\pi *36.30}[/tex] ,

the revolution angle made by the tire =

[tex]=2\pi * \frac{63360}{\pi 36.60}[/tex]

[tex]=2 * \frac{63360}{ 36.60}[/tex]

[tex]= 3491.91[/tex] radian

Calculate the area of triangle OPQ.

Answers

Thus, we need information about the sides OQ and PQ to solve the triangle and find the area. The information given is not enough to determine the area of the triangle.

Is this triangle solvable?

In this question we must analyze if the area of the triangle OPQ can be found by all information given. By the law of the cosines we understand that lengths of two sides and the measure of an angle should be known to construct a triangle and by the law of the sines we understand that either two angles and a side or two sides and an angle must be known.

Thus, we need information about the sides OQ and PQ to solve the triangle and find the area. The information given is not enough to determine the area of the triangle.

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The______is the set of inputs For a fraction

Answers

The set of all input values of a function is the domain of the function

What is a function?

A function relates an input to an output.

A function defines a relationship between one variable (the independent variable) and another variable.

The set of all input values of a function is the domain of the function.

The domain of a function are also called independent variables.

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NEED HELP ASAP!!!!!!!!
PLEASE

For which set of data are the median and mode the same number?
(A) 4, 5, 7, 8, 9, 9
(B) 4, 5, 7, 7, 8, 10
(C) 3, 5, 6, 8, 8, 9
(D) 5, 5, 6, 8, 9, 10

Answers

Answer:

b

Step-by-step explanation:

Express a) 36 b) 80 as sum of two prime numbers

Answers

⊱________________________________________________________⊰

Answer:

See below.

Step-by-step explanation:

[tex]\large\begin{gathered} \sf{36=19+17. 19 \ and \ 17 \ are}\\ \sf{\ both \ primes, \ because \ they're \ only \ divisible \ by \ 1 \ and \ themselves} \\ \sf{ 80=73+7. \ Again, \ 73 \ and \ 7 \ \underline{ARE} \ prime. \end{gathered}}[/tex].

Done!!

⊰________________________________________________________⊱

Cαlligrαphy

In the falcon's nest ice cream cost 20 cents. if the school pays 15 cents, what percent mark-up is it?

Answers

Answer: 25% off

Step-by-step explanation:

1= 0.25 + 0.75

25% is off is the equivalency of multiplying the value of the original cost with 0.75.

20*0.75=15

Evaluate 43 – 3m for m = 6.

Answers

Step by step explanation:
Original Equation: 43 - 3m; m = 6
Substitute 6 in for m
43 - 3(6)

Multiply 3*6
43 - 18

Subtract 43 - 18
25

Your answer is: 25

Answer:

= 43 - 3×6= 43 - 18

Therefore , 25 ans.

Try it
Which graph represents the function h(x) = 5.5|x]?
LIV
-2
2 4
-4-2
Intro
2
-4-2
O
2 4
-4-2
2

Answers

[tex]take \: some \: values \\ h(1) = 5.5 \times |1| = 5.5 \times 1 = 5.5 \\h(2) = 5.5 \times |2| = 5.5 \times 2 = 11 \\ h(4) = 5.5 \times |4| = 5.5 \times 4= 22[/tex]

It's clearly the second option since the other ones aren't steep enough.

Fill the empty slots by dragging tiles from the left to show the next step for solving the equation. Solve the two-step equation. -9x + 0.4 = 4
Which operation must be performed to move all the constants to the right side of the equation?

Answers

In order to move a the constant terms to the right hand side, we need to subtract 0.4 from both sides of the equation.

What are the constant terms?

In an equation, the constant terms are those terms that do not have any alphabet attached to them. In this case, 4 and 0.4 are constant terms.

In order to move a the constant terms to the right hand side, we need to subtract 0.4 from both sides of the equation thus;

-9x + 0.4 - 0.4 = 4 - 0.4

-9x = 3.6

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ABC is an equilateral triangle whose vertex A has the co-ordinates (0, √3). Find the co- ordinates of B and C. ​

Answers

Answer:

B = (-1, 0)

C = (1, 0)

Step-by-step explanation:

Properties of an Equilateral Triangle

Three sides of equal lengthAll interior angles are 60°

Given:

ΔABC is an equilateral triangleVertex A is at (0, √3)

Drawing an altitude from vertex A divides the triangle into two 30-60-90 triangles.

A 30-60-90 triangle is special right-angled triangle where:

Angles are in the ratio 1 : 2 : 3Sides are in the ratio 1 : √3 : 2

Therefore, the formula for the sides is: b : b√3 : 2b, where:

b = shortest side opposite the 30° angleb√3 = side opposite the 60° angle2b = longest side (hypotenuse) is opposite the right angle

As Vertex A has the co-ordinates (0, √3), the side opposite the 60° angle is √3 units.

Using the ratios to find b (shortest side length):

b√3 = √3  ⇒  b = 1

As the altitude divides BC into two equal line segments, and the length of the shortest side of the right triangles is 1 unit, the coordinates of B are C are:

B = (-1, 0)C = (1, 0)

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Which of the following could be rewritten as an addition problem of two integers with the same sign?

8 - 10
-8 - 10
-8 + 10
-8 - (-8)

Answers

-8-10
because it can also be written as -8 + -10 instead of -8 - 10

change the unit of weight 1,000 lb =___ t ?

Answers

Answer:

0.5 t

Step-by-step explanation:

Since we know that 2,000lbs=1 t
1,000lbs is half a ton, which makes it 0.5 tons

Other Questions
The sum of a number and 6 is at least 15.??? Marijuana in its herbal form, is a psychoactive product of the plant Cannabis sativa. true or false A Three-Point TurnChapter 1"You know, hardly anyone ever needs to do a three-point turn anymore," said Justin, trying to help Becky calm down."Oh, so it's not a useful skill AND I am probably going to fail the driving test because I can't do it anyway," Becky said, raising her voice for emphasis. "That should make me feel like a million bucks when I flunk."Justin was riding with Becky so she could take her driving test. He had volunteered for the job because he thought she would be less nervous with him than with their mom, but so far, he wasn't sure he was making any difference."Slow down, your turn is coming up here," he said, looking ahead."I know, I know," she replied, "I've been here before rememberthe last time I flunked."Justin was pretty sure if he had let her miss the turn, things would only have deteriorated further, but he wasn't sure he was fond of being the scapegoat for Becky's anxiety."Listen, you need to take a few deep breaths," he said, hoping he could help her at least relax a bit. "Being nervous won't help you with the three-point turn or anything else you have to do. Hey, did you just take that turn without your turn signal on?" This was going to be harder than he thought."Stop yelling at me," Becky replied, clearly frustrated, "I can't concentrate.""Look, you need to stop and get yourself together here," Justin started. "It is not just about passing the driving test. I don't want to get in an accident, so pull into that parking lot."Becky drove into the office building's parking lot where Justin was pointing. Justin knew they were less than a mile from the licensing office, and if she continued in this condition, he'd be having this same discussion three months from now when she tried the test again for the third time."You need to get a grip," he started after she put the car in park, "because you have studied and practiced driving all year. You know this stuff inside and out, backwards and forwards. What are you so nervous about?""I don't know, I don't know," Becky wailed, resting her head on the steering wheel. "I just get so tired of failing."Listening quietly as Becky sobbed, Justin realized this was about much more than a driving test. He also knew if he didn't find a way to help Becky things would just get worse.Chapter 2Justin took a deep breath and collected his thoughts. Becky was an unbelievably consistent straight-A student. It was Justin who got the bad grades in school, and Justin who had to repeat every math class he'd ever taken. It was Justin who wished he could get the grades Becky got. Some things came easier for Justin: He was athletic, handy with tools, and good at making the best of whatever life threw at him. Mom called him her "lemons into lemonade" kid. But for the most part, Becky succeeded easily, whereas Justin had to work and work to just get a passing grade.Rather than having Becky catalogue all the things she supposedly "failed" at, Justin decided to try an alternative approach, one that wouldn't remind him of all the ways he had failed."Okay, Becky, let's assume for a moment you fail this test again. What is the worst thing that could happen?" he asked."I would be the oldest kid at school without a license and be humiliated," she replied. Justin thought he heard a bit of panic in her voice but continued with his plan."Yes, but won't we still have to drive to school together for at least one more year anyway?" he asked."Yes, but..." she started."And who will know, if you don't tell anyone except your friends, that you don't have your license? You know Mom can't afford another car just for you, right?""Yes," she said quietly."So what difference does it make, really," he said. "Another three months to wait in the grand scheme of your life doesn't seem like all that long, right?""I suppose not," she said.Justin could tell she was breathing more slowly now. "Besides," he said, "I would miss all the practice driving with you," and for good measure he reached over and pinched her arm."Ow," she said, hitting back at him, "that hurt.""So let's go do this, okay?"Okay," she said. Becky cranked up the car, backed slowly out of the parking spot and drove up to the parking lot's exit. 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