Question: “use calculator to find the measure of angle A round to the nearest tenth”
(please show work if you can)

The correct statements are a and b. Statement d is incorrect as the training data set is used to build the model, not to test its prediction accuracy.

The data should be partitioned into training and validation sets because we need two sets of data: one to build the model that depicts the relationship between the predictor variable(s) and the predicted variable, and another to validate the model's predictive accuracy. The training data set is used to build the model, and the validation data set is used to test the prediction accuracy of the model. In this process, the model (built using the training data set) is used to make predictions with the validation data - data that were not used to fit the model. In this way, we get an unbiased estimate of how well the model performs. Therefore, the correct statements are a and b. Statement d is incorrect as the training data set is used to build the model, not to test its prediction accuracy.
Your answer: a and b are the correct statements.

a. The training data set is used to build the model, and the validation data is used to test the prediction accuracy of the model.
b. In this process, the model (built using the training data set) is used to make predictions with the validation data - data that were not used to fit the model. In this way, we get an unbiased estimate of how well the model performs.
c. The data should be partitioned into training and validation sets because we need two sets of data: one to build the model that depicts the relationship between the predictor variables and the predicted variable, and another to validate the model's predictive accuracy.

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Emma is currently 21 years old.

Let's denote Emma's age as E and Claire's age as C. We are given the following information:

The age of a person can be counted differently in different cultures. This calculator is based on the most common age system. In this system, age increases on a person's birthday. For example, the age of a person who has lived for 3 years and 11 months is 3, and their age will increase to 4 on their next birthday one month later. Most western countries use this age system.

1. When Emma was born, Claire was E years old.
2. Currently, Claire is 42 years old (C = 42).

Since Emma is currently the same age as Claire was when Emma was born, we can say E = C - E.

Now let's solve for E:

E = 42 - E
2E = 42
E = 21

So, Emma is currently 21 years old.

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Step-by-step explanation:

I'm sorry, but I would need some additional information to determine when Maya arrived in L.A. Specifically, I would need to know the distance from Maya's starting point to L.A. Without knowing this distance, it is not possible to determine how long the journey would take and what time Maya would arrive.

However, if we assume that the distance from Maya's starting point to L.A. is 400 km, for example, then we can calculate that she would arrive at 8:00 pm (6 hours after starting) by dividing the distance by her speed:

Time = Distance ÷ Speed

Time = 400 km ÷ 80 km/h

Time = 5 hours

Since Maya started driving at 2 pm, we can add the 5 hours of driving time to find that she would arrive at 7 pm:

Arrival time = Starting time + Driving time

Arrival time = 2 pm + 5 hours

Arrival time = 7 pm

Again, please note that the actual arrival time would depend on the actual distance between Maya's starting point and L.A.

As R² with the given operations satisfies all the vector space axioms, it is indeed a vector space.

To determine whether the set R² with the given operations is a vector space, we need to verify if it satisfies all the vector space axioms.

1. Closure under addition: (x1, y1) + (x2, y2) = (x1 + x2, y1 + y2), which is of the same form as the original elements in R². Thus, addition is closed.

2. Commutativity of addition: (x1, y1) + (x2, y2) = (x1 + x2, y1 + y2) = (x2 + x1, y2 + y1) = (x2, y2) + (x1, y1). Thus, addition is commutative.

3. Associativity of addition: ((x1, y1) + (x2, y2)) + (x3, y3) = (x1 + x2, y1 + y2) + (x3, y3) = (x1 + x2 + x3, y1 + y2 + y3) = (x1, y1) + (x2 + x3, y2 + y3) = (x1, y1) + ((x2, y2) + (x3, y3)). Thus, addition is associative.

4. Identity element of addition: The additive identity is (0, 0), since (x, y) + (0, 0) = (x + 0, y + 0) = (x, y) for any (x, y) in R².

5. Inverse elements of addition: The additive inverse of (x, y) is (-x, -y), since (x, y) + (-x, -y) = (x - x, y - y) = (0, 0).

6. Closure under scalar multiplication: c(x, y) = (cx, cy), which is of the same form as the original elements in R². Thus, scalar multiplication is closed.

7. Distributivity of scalar multiplication over vector addition: c((x1, y1) + (x2, y2)) = c(x1 + x2, y1 + y2) = (c(x1 + x2), c(y1 + y2)) = (cx1 + cx2, cy1 + cy2) = (cx1, cy1) + (cx2, cy2) = c(x1, y1) + c(x2, y2). Thus, scalar multiplication is distributive over vector addition.

8. Distributivity of scalar multiplication over scalar addition: (c1 + c2)(x, y) = ((c1 + c2)x, (c1 + c2)y) = (c1x + c2x, c1y + c2y) = c1(x, y) + c2(x, y). Thus, scalar multiplication is distributive over scalar addition.

9. Associativity of scalar multiplication: c1(c2(x, y)) = c1(c2x, c2y) = (c1c2x, c1c2y) = (c1c2)(x, y). Thus, scalar multiplication is associative.

10. Identity element of scalar multiplication: The multiplicative identity is 1, since 1(x, y) = (1x, 1y) = (x, y) for any (x, y) in R².

Since R² with the given operations satisfies all the vector space axioms, it is indeed a vector space.

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Tthe 99th percentile for the average number of residents within five miles of each store in a sample of 50 stores is: x = μ + z*SE = 17 + 2.326*0.4949 = 18.1662. Rounding to the nearest tenth, the answer is 18.2 thousand residents.

To find the 99th percentile for the average number of residents within five miles of each store in a sample of 50 stores, we need to use the z-score formula:

z = (X - μ) / (σ / √n)

In this case, the mean (μ) is 17,000 and the standard deviation (σ) is 3,500. The sample size (n) is 50 stores.

First, we need to find the z-value for the 99th percentile. Based on the z-table, the z-value for the 99th percentile is approximately 2.33.

Now we can use the z-score formula to find X, the 99th percentile for the average number of residents:

X = μ + z * (σ / √n)

X = 17,000 + 2.33 * (3,500 / √50)

X = 17,000 + 2.33 * (3,500 / 7.071)

X = 17,000 + 2.33 * 495.4

X = 17,000 + 1,153.4

X = 18,153.4

Since we need to provide the answer in thousands and round to the nearest tenth, the 99th percentile for the average number of residents within five miles of each store in a sample of 50 stores is approximately 18.2 thousand residents.

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Answer:

a=8c-b/2

Step-by-step explanation:

a/2c+b/4=2

find the lcm

lcm=4c

multiply through by lcm 4c

4c×a/2c+4c ×b/4=4c×2

2×a+b×c=8c

2a+bc=8c

subtract bc from both sides

2a+bc-bc=8c-bc

2a=8c-b

To make 'a' subject of formula, divide 2 from both sides

2a/2=8c-b/2

a=8c-b/2

The number of dimes students has is 12 dimes.

We are given that;

Ratio= 2:3

Cost= $1.60

This is a question that can be solved using a system of linear equations. Let x be the number of nickels and y be the number of dimes. Then we have:

0.05x+0.10y=1.60

for the total amount of money, and

yx​=32​

for the ratio of nickels to dimes. To solve this system, we can use the substitution method. First, we isolate x in the second equation:

x=32​y

Then we substitute this expression for x in the first equation:

0.05(32​y)+0.10y=1.60

Simplifying, we get:

301​y+101​y=1.60

Adding the fractions, we get:

304​y=1.60

Multiplying both sides by 30, we get:

4y=48

Dividing both sides by 4, we get:

y=12

The student has 12 dimes.

Therefore, by the given ratio the answer will 12 dimes.

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The general solution to the differential equation y''' - 2y'' - 8y = 0 is [tex]y(t) = c1 e^{(4t)} + c2 e^{(-t)} + c3 t e^{(-t).[/tex]

To find the general solution of the given differential equation:

y''' - 2y'' - 8y = 0

We first find the characteristic equation by assuming a solution of the form:

y = [tex]e^{(rt)}[/tex]

where r is a constant to be determined.

Substituting this solution into the differential equation, we get:

[tex]r^3 e^{(rt)} - 2r^2 e^{(rt)} - 8e^{(rt)} = 0[/tex]

Dividing both sides by [tex]e^{(rt)[/tex], we get:

r³ - 2r² - 8 = 0

This is the characteristic equation, which we can solve for r using factoring or the quadratic formula. Factoring gives:

(r - 4)(r + 1)² = 0

So the roots are:

r = 4 (with multiplicity 1)

r = -1 (with multiplicity 2)

Therefore, the general solution to the differential equation is:

[tex]y(t) = c1 e^{(4t)} + c2 e^{(-t)} + c3 t e^{(-t).[/tex]

where c1, c2, and c3 are constants determined by the initial or boundary conditions of the problem.

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A committee consists of 11 men and 12 women. In 304,920 ways can a subcommittee of 4 men and 6 women be chosen

To solve this problem, we will use the combination formula:

nCr = n! / (r! * (n-r)!)

where n is the total number of people (in this case, 23), r is the number of people we want to choose (4 men and 6 women), and ! means factorial (the product of all positive integers up to that number).

First, we need to find the number of ways we can choose 4 men from the 11 available. This is:

11C4 = 11! / (4! * 7!) = 330

Next, we need to find the number of ways we can choose 6 women from the 12 available. This is:

12C6 = 12! / (6! * 6!) = 924

To find the total number of ways we can choose a subcommittee of 4 men and 6 women, we need to multiply these two numbers:

330 * 924 = 304,920

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Answer:

2(3/8) + 4/8 + 5/8 + 7/8

= 6/8 + 4/8 + 5/8 + 7/8 = 22/8 = 2 6/8

B is correct.

The statement that is true about the quadrilateral is

It is a rectangle because the opposite sides in a quadrilateral are congruent.

Option C is the correct answer.

We have,

From the given information,

AB = CD = √73

BC = AD = √5

Slope:

BA = CD = 1/2

BC = AD = 8/3

Now,

This means,

AB = CD = congruent

BC = AD = congruent

Now,

The opposite sides in a quadrilateral are congruent.

This means,

The quadrilateral is a rectangle.

Thus,

The statement that is true about the quadrilateral is

It is a rectangle because the opposite sides in a quadrilateral are congruent.

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The Wronskian of the functions e and e(3x) is 2e(4x).

The Wronskian of the functions e^x and e^(3x) is found by computing the determinant of the matrix formed by their derivatives. In this case, the Wronskian is:

W(e^x, e^(3x)) = |(d/dx)e^x   (d/dx)e^(3x)|
                      |e^x         3e^(3x)|

Now, compute the determinant:

W(e^x, e^(3x)) = e^x(3e^(3x)) - e^(3x)e^x
W(e^x, e^(3x)) = 2e^(4x)

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To find the answers, we need to calculate the number of steps each player takes before they are unable to continue:

For Amar:

5 stairs up and 2 stairs down per turn

Net gain of 3 stairs per turn

It will take 32 turns to reach 96 stairs (32 * 3 = 96)

In the 33rd turn, Amar will climb 5 stairs and reach 100 stairs.

For Akbar:

7 stairs up and 2 stairs down per turn

Net gain of 5 stairs per turn

It will take 19 turns to reach 95 stairs (19 * 5 = 95)

In the 20th turn, Akbar will climb 7 stairs and reach 100 stairs.

For Anthony:

10 stairs up and 3 stairs down per turn

Net gain of 7 stairs per turn

It will take 14 turns to reach 98 stairs (14 * 7 = 98)

In the 15th turn, Anthony will climb 10 stairs and reach 100 stairs.

I) The players will meet on the same stair whenever they end up on a stair whose number is the same for any two players. To find out the number of times they meet on the same stair, we need to calculate the lowest common multiple (LCM) of the number of turns taken by each player to reach 100 stairs.

Amar takes 33 turns

Akbar takes 20 turns

Anthony takes 15 turns

LCM(33,20,15) = 660

Therefore, they will meet on the same stair 660/33 + 660/20 + 660/15 = 20 + 33 + 44 = 97 times.

II) Anthony takes the least number of steps to reach near hundred, as he only needs 15 turns to reach 98 stairs.

Answer:

The median is number 12!!!!

The population density for each animal is given as follows:

The population density is calculated as the division of the total population by the total area.

The area for this problem is given as follows:

2.22 million acres = 2,220,000 acres.

Hence the densities are given as follows:

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Based on the given sample, the number of voters vote for the incumbent are 1,200,000.

Based on the sample, it can be estimated that approximately 1,200,000 of the 2,000,000 voters will vote for the incumbent.

This can be calculated by taking the sample size of 10 and multiplying it by the proportion of votes that the incumbent received (6/10).

This gives a result of 6/10 x 2,000,000 = 1,200,000.

However, it is important to note that this is just an estimate and the actual number of votes for the incumbent could be higher or lower than 1,200,000.

Therefore, based on the given sample, the number of voters vote for the incumbent are 1,200,000.

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5x - y - 13 = 0  is the equation of the plane

To find the equation of the plane, we need two pieces of information: a point on the plane, and the normal vector of the plane.

We are given a point on the plane: P0(2, -3, -5).

To find the normal vector of the plane, we need to use the fact that the plane is perpendicular to the given line. The direction vector of the line is <1, 5, 0>, since the line has parametric equations x=2+t, y=-3+5t, z=-3, and the vector <1, 5, 0> is the coefficient vector of the parameter t in these equations.

Any vector that is perpendicular to <1, 5, 0> will be a normal vector of the plane. One such vector is <5, -1, 0>, which we can verify by taking the dot product of this vector with <1, 5, 0>:

<5, -1, 0> · <1, 5, 0> = 5(1) + (-1)(5) + 0(0) = 0

Thus, the normal vector of the plane is <5, -1, 0>.

Now we can use the point-normal form of the equation of a plane:

ax + by + cz = d

where <a, b, c> is the normal vector of the plane, and (x, y, z) is any point on the plane. Substituting in the values we have:

5(x - 2) - 1(y + 3) + 0(z + 5) = 0

Simplifying:

So the equation of the plane is:

5x - y - 13 = 0

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Answer:

x = 30 , interior angle = 120

Step-by-step explanation:

the sum of the exterior angles of a polygon = 360°

since the hexagon is regular then exterior angles are congruent , then

6 × 2x = 360

12x = 360 ( divide both sides by 12 )

x = 30

then each exterior angle = 2x = 2 × 30 = 60°

the sum of exterior angle and interior angle = 180° , that is

interior angle + 60° = 180° ( subtract 60° from both sides )

interior angle = 120°

Answer:

4°C

Step-by-step explanation:

-8 + 12 = 4°C

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Answer:

The highlighted part is the answer

Step-by-step explanation:

Mark needs to add heat to the solution in order to elevate the temperature from -4.3°C to a positive value

The amount of heat needed to increase a substance's temperature by one degree Celsius per gramme is known as its specific heat capacity. It is a characteristic of a substance that is intense and independent of the size or shape of the quantity under consideration. A substance's specific heat capacity is typically indicated by the letters "c" or "s"².

Mark needs to add heat to the solution in order to elevate the temperature from -4.3°C to a positive value.

. The bulk of the solution and its specific heat capacity affect the amount of heat needed.

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A) The estimated cost per year for Jorden would be:

   $X - ($7,500 + $3,700)

B) Jo needs to contribute each year:

    65% of $Y = 0.65 * $Y

Estimating cost means to calculate the approximate amount of money required for a particular expense or project.

It may involve considering various factors, such as known costs, expected expenses, and potential variables that may affect the final cost.

To estimate Jorden's cost per year, we need to subtract the scholarships, grants, and work-study earnings from the total cost of attendance. Let's assume the total cost of attendance is $X.

Given:

Scholarships and grants = $7,500 per year

Work-study earnings = $3,700 per year

So, the estimated cost per year for Jorden would be:

$X - ($7,500 + $3,700)

B) To calculate Jo's contribution, we need to find 65% of the estimated cost per year. Let's assume the estimated cost per year is $Y.

Given:

Estimated cost per year = $Y

Family contribution percentage = 65%

So, Jo's contribution per year would be:

65% of $Y = 0.65 * $Y

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Jamal would need approximately 7.9 gallons of gas to travel 296.25 miles.

We can use the concept of direct variation to solve this problem. Direct variation means that two quantities are related by a constant ratio. In this case, the number of miles driven is directly proportional to the number of gallons used.

To find the constant of proportionality, we can use the given data. From the table, we can see that when Jamal used 14 gallons, he drove 525 miles. So we can write:

14/525 = k

where k is the constant of proportionality.

Solving for k, we get:

k = 14/525

Now we can use this value of k to find how many gallons Jamal would need to travel 296.25 miles. Let x be the number of gallons he would need. Then we can write:

x/296.25 = k

Substituting the value of k, we get:

x/296.25 = 14/525

Solving for x, we get:

x = (296.25 × 14) / 525

x ≈ 7.9

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The sequence an=(9n)/√(n^2+1) converges to 9/sqrt(1+1)=9/sqrt(2)=9√2/2, so the answer is (a) converges to (9√2)/2.

To see why, we can use the limit comparison test, comparing to a similar sequence bn = 9n/sqrt(n^2), which simplifies to bn = 9/sqrt(n). Since the limit as n approaches infinity of bn is 0, we can use this to find the limit of an by taking the limit of the ratio an/bn:

lim(n->inf) an/bn = lim(n->inf) [(9n)/√(n^2+1)] / [9/sqrt(n)]
= lim(n->inf) sqrt(n) * (n/sqrt(n^2+1))
= lim(n->inf) (n/sqrt(n^2+1)) (since sqrt(n) approaches infinity as n approaches infinity)
= lim(n->inf) (1/sqrt(1+(1/n^2))) = 1/sqrt(1+0) = 1/sqrt(1) = 1.

Since this limit is finite and nonzero, we can conclude that the sequence converges, and its limit is 9/sqrt(2).

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David gained approximately $2,155.06 in interest after 4 years.

By utilizing the compound interest formula A = P(1 + r/n)^(nt), one can determine the future value of an investment or loan, inclusive of its added interest.

Variables to consider include the initial deposit (P), annual interest rate (r as a decimal), frequency at which it is compounded per year (n) and time (t).

This specific scenario assimilates a principal amount of $10,000 with an annual interest rate of 5% compounded yearly for four years, resulting in an accrued balance of roughly $12,155.06.

Therefore, David gained approximately $2,155.06 in interest after 4 years.

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If David deposited $10,000 into a bank account with a 5% interest rate compounded annually, how much interest did he gain after 4 years?

The magnitude of an earthquake 25 times as strong as a 4.2 earthquake would be 6.3 on the Richter scale. If a small earthquake measures 4.2 on the Richter scale, the magnitude of an earthquake 25 times as strong will be 6.3 on the Richter scale.

The Richter scale measures the magnitude of an earthquake, which is a logarithmic scale. This means that each increase of one on the Richter scale corresponds to a ten-fold increase in the amplitude of the earthquake waves.
If a small earthquake measures 4.2 on the Richter scale, an earthquake 25 times as strong would have an amplitude that is 25 times greater than the amplitude of the 4.2 earthquakes.
To find the magnitude of the stronger earthquake, we need to determine how many times greater the amplitude of the 25 times stronger earthquake is than the amplitude of the 4.2 earthquakes.
25 times stronger = 25 x 10 = 250 (because each increase of one on the Richter scale corresponds to a ten-fold increase in amplitude)
So the magnitude of the 25 times stronger earthquake can be calculated using the formula:
M2 = M1 + log(A2/A1)
Where M1 is the magnitude of the 4.2 earthquakes, A1 is its amplitude, A2 is the amplitude of the 25 times stronger earthquake, and M2 is the magnitude we want to find.
Substituting the values we have:
M1 = 4.2
A1 = 1 (by definition)
A2 = 250
M2 = 4.2 + log(250/1)
M2 = 6.3
Therefore, the magnitude of an earthquake 25 times as strong as a 4.2 earthquake would be 6.3 on the Richter scale.

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The best graph to display the data is C. a bar graph titled favorite topping with the x axis labeled topping and the y axis labeled number of customers, with the first bar labeled chocolate chips going to a value of 17, the second bar labeled hot fudge going to a value of 12, the third bar labeled nuts going to a value of 27, and the fourth bar labeled sprinkles going to a value of 44.

Categorical data is best represented through a bar graph wherein every distinctive category is illustrated by a rectangular bar in correspondence to the frequency or item count. This display method uses the height or length of each rectangle as its basis.

The customer's preferences on their choice of ice cream toppings were subjected to a categorical survey; hence, it deemed suitable for visual illustration via a bar chart. There are four recognizable component ingredients identified in this survey namely: Sprinkles, Nuts, Hot Fudge, and Chocolate Chips. Each component underlies particular statistical value and described discretely hence a bar graph proves fitting to portray this information.

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The parameterization of the portion of the circular cylinder is :

x = 4 cos(t) cos(theta)
y = ±1/sin(theta)
z = 4 cos(t) sin(theta)
where t varies from 0 to pi/3 and theta varies from 0 to pi/6.

To find a parameterization of the portion of the circular cylinder y2 z2=16 between the planes x=2 and x=6, we can use cylindrical coordinates. Let r be the radius of the cylinder, and let theta be the angle of rotation around the z-axis. Then, we can parameterize the cylinder as:

x = r cos(theta)
y = y
z = r sin(theta)

Since we want the portion of the cylinder between x=2 and x=6, we can set x=r cos(theta) equal to these values:

2 = r cos(theta)
6 = r cos(theta)

Solving for r in each equation, we get:

r = 2/cos(theta)
r = 6/cos(theta)

Since the cylinder has radius sqrt(16) = 4, we know that r must be between 2 and 4. Therefore, we can set:

r = 4 cos(t)

where t is a parameter that varies from 0 to pi/3 (corresponding to theta varying from 0 to pi/6). Substituting this expression for r into the parameterization above, we get:

x = 4 cos(t) cos(theta)
y = y
z = 4 cos(t) sin(theta)

To find the range of y, we can look at the equation y2 z2=16 and substitute the expressions for y and z above:

y2 (4 cos(t) sin(theta))2 = 16
y2 sin2(theta) = 1
y = ±1/sin(theta)

Since theta varies from 0 to pi/6, sin(theta) varies from 0 to 1/2, so y varies from -2 to -∞ and from 2 to +∞. Therefore, we can write the parameterization as:

x = 4 cos(t) cos(theta)
y = ±1/sin(theta)
z = 4 cos(t) sin(theta)

where t varies from 0 to pi/3 and theta varies from 0 to pi/6.

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This matrix can be used to perform the reflection of any vector in the line y = x, by multiplying the vector by the matrix.

What is Matrix?

A matrix is a rectangular array or table of numbers or symbols that are arranged in rows and columns. The numbers or symbols in a matrix are called its elements or entries. Matrices are used in various areas of mathematics, science, engineering, and other fields to represent and manipulate data, perform transformations, solve equations, and model real-world phenomena.

To find the standard matrix of the given linear transformation from[tex]R^{2}[/tex] to [tex]R^{2}[/tex] we can use the fact that the standard basis vectors i = (1, 0) and j = (0, 1) are transformed into the vectors that are reflections of themselves in the line y = x.

The image of i is obtained by reflecting i across the line y = x, which gives us the vector (0, 1). Similarly, the image of j is obtained by reflecting j across the line y = x, which gives us the vector (1, 0).

Therefore, the standard matrix of the linear transformation is:

| 0 1 |

| 1 0 |

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