A cistern is to be built of cement. The walls and bottom will be 1 foot thick. The outer height will be 20 feet. The inner diameter will be 10 feet. To the nearest cubic foot, how much cement will be needed for the job? Use 3. 14 for π

La probabilidad de sacar un producto defectuoso al azar de las tres cajas es aproximadamente 0.0917, o un 9.17%.

La probabilidad de sacar un producto defectuoso al azar de las tres cajas se puede calcular utilizando la fórmula de la probabilidad.

Primero, calculemos la probabilidad de sacar un producto defectuoso de cada caja:

1. En la primera caja, hay 3 productos defectuosos entre 20 productos en total. La probabilidad es 3/20.

2. En la segunda caja, hay 2 productos defectuosos entre 16 productos en total. La probabilidad es 2/16.

3. En la tercera caja, no hay productos defectuosos entre 10 productos en total. La probabilidad es 0/10.

Para encontrar la probabilidad total, sumamos las probabilidades de cada caja y luego dividimos por el número total de cajas:

(3/20 + 2/16 + 0/10) / 3 ≈ (0.15 + 0.125 + 0) / 3 ≈ 0.0917

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The maximum and minimum values for given function f(x, y) = 5x² + 5y² subject to xy = 1 are both 10. The extreme values of f(x, y, z) = x + 2y; x + y + z = 6, y² + z² = 4 subject to both constraints are 7 and -4.

We can use Lagrange multipliers to find the maximum and minimum values of f(x, y) subject to the constraint xy = 1.

First, we set up the Lagrange function

L(x, y, λ) = 5x² + 5y² + λ(xy - 1)

Then, we take partial derivatives of L with respect to x, y, and λ and set them equal to 0

∂L/∂x = 10x + λy = 0

∂L/∂y = 10y + λx = 0

∂L/∂λ = xy - 1 = 0

Solving these equations simultaneously, we get

x = ±√2, y = ±√2, λ = ±5/2√2

We also need to check the boundary points where xy = 1, which are (1, 1) and (-1, -1). We evaluate f at these points and compare them to the values we get from the Lagrange multipliers.

f(√2, √2) = 10, f(-√2, -√2) = 10

f(1, 1) = 10, f(-1, -1) = 10

So the maximum and minimum values of f(x, y) subject to xy = 1 are both 10.

We can use Lagrange multipliers to find the extreme values of f(x, y, z) subject to both constraints.

First, we set up the Lagrange function

L(x, y, z, λ, μ) = x + 2y + λ(x + y + z - 6) + μ(y² + z² - 4)

Then, we take partial derivatives of L with respect to x, y, z, λ, and μ and set them equal to 0

∂L/∂x = 1 + λ = 0

∂L/∂y = 2 + λ + 2μy = 0

∂L/∂z = λ + 2μz = 0

∂L/∂λ = x + y + z - 6 = 0

∂L/∂μ = y² + z² - 4 = 0

Solving these equations simultaneously, we get

x = -1, y = 2, z = 3, λ = -1, μ = -1/2

x = 3, y = -2, z = -1, λ = -1, μ = -1/2

We also need to check the boundary points where either x + y + z = 6 or y² + z² = 4. These points are (0, 2, 2), (0, -2, -2), (4, 1, 1), and (4, -1, -1). We evaluate f at these points and compare them to the values we get from the Lagrange multipliers.

f(-1, 2, 3) = 7, f(3, -2, -1) = -1

f(0, 2, 2) = 4, f(0, -2, -2) = -4

f(4, 1, 1) = 6, f(4, -1, -1) = 2

So the maximum value of f subject to both constraints is 7, which occurs at (-1, 2, 3), and the minimum value of f subject to both constraints is -4, which occurs at (0, -2, -2).

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The width of the rectangle is approximately 5.39 meters.

Let's denote the width of the rectangle by x. According to the problem, the length of the rectangle is 4 meters more than the width, which means that the length can be represented as x+4.

The formula for the area of a rectangle is A = length x width. In this case, we know that the area of the rectangle is 77 square meters, so we can set up the following equation:

77 = (x+4)x

Expanding the brackets, we get:

77 = x² + 4x

Rearranging this equation into standard quadratic form, we get:

x² + 4x - 77 = 0

To solve for x, we can use the quadratic formula:

[tex]x = \frac{(-b ± sqrt(b^2 - 4ac))}{ 2a}[/tex]

Plugging in the values for a, b, and c, we get:

[tex]x = \frac{(-4 ± sqrt(4^2 - 4(1)(-77)))}{ 2(1)}[/tex]

Simplifying this expression, we get:

[tex]x = \frac{(-4 ± sqrt(336)} { 2}[/tex]

[tex]x = \frac{(-4 ± 4sqrt(21))}{ 2}[/tex]

x = -2 ± 2[tex]\sqrt{(21)}[/tex]

Since the width of a rectangle cannot be negative, we discard the negative solution and get:

x = -2 ± 2[tex]\sqrt{(21)}[/tex]

Therefore, the width of the rectangle is approximately 5.39 meters (rounded to two decimal places).

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The function g(x)=-1/2f(x)+3 containing points (a) (0, 4) and (a) (2, 0).

The function g(x) = -1/2f(x) + 3 is obtained by applying certain transformations to the original function f(x) = 3^x - 3.

To find the points on the graph of g(x), we need to substitute the x-values from the given points into the function g(x) and determine the corresponding y-values.

Given:

Original function f(x) = 3^x - 3

Points on f(x): (0, -2) and (2, 6)

To find the points for g(x), we substitute the x-values into g(x) = -1/2f(x) + 3:

1. For the point (0, -2):

g(0) = -1/2f(0) + 3

      = -1/2(-2) + 3

      = 1 + 3

      = 4

2. For the point (2, 6):

g(2) = -1/2f(2) + 3

      = -1/2(6) + 3

      = -3 + 3

      = 0

Therefore, the points for the function g(x) = -1/2f(x) + 3 are:

(a) (0, 4)

and

(a) (2, 0)

Hence, the correct answer is:

(a) (0, 4) and (a) (2, 0).

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The equations that have the same value of x as 3/5 (30 x - 15) = 72 are C, D, and E.

To solve for x in 3/5 (30 x - 15) = 72, we can first simplify the left side by distributing the 3/5:

3/5 (30 x - 15) = 18 x - 9

Now we can solve for x by setting the right side equal to 72:

18 x - 9 = 72

Adding 9 to both sides:

18 x = 81

Dividing by 18:

x = 4.5

So we know that option E is one of the correct answers.

To check which of the other options have the same value of x, we can substitute x = 4.5 into each equation and see if it simplifies to 72:

A. 18 x - 15 = 72

18(4.5) - 15 = 72

81 - 15 = 72 (not equivalent)

B. 50 x - 25 = 72

50(4.5) - 25 = 200 - 25 = 175 (not equivalent)

C. 18 x - 9 = 72

18(4.5) - 9 = 72 (equivalent)

D. 3 (6 x - 3) = 72

3(6(4.5) - 3) = 3(24) = 72 (equivalent)

Therefore, the equations that have the same value of x as 3/5 (30 x - 15) = 72 are C, D, and E.

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Its translation is 5×3-3=12

The correct expression that is equal to 4.6 is option c. [1.6 + (3 × 4)] – (2 ÷ 2)

Let's evaluate each expressions using the BODMAS rule of mathematics,

a. 1.6 + (3 × 4) – 2 ÷ 2

= 1.6 + 12 - 1

= 12.6

b. 1.6 + 3 × 4 – 2 ÷ 2

= 1.6 + 12 - 1

= 12.6

c. [1.6 + (3 × 4)] – (2 ÷ 2)

= [1.6 + 12] - 1

= 12.6

d. (1.6 + 3) × (4 – 2) ÷ 2

= 4.6 × 2 ÷ 2

= 4.6

BODMAS is an acronym used to remember the order of operations in mathematics: Brackets, Orders, Division, Multiplication, Addition, Subtraction. It is used to perform calculations in the correct order to obtain the correct result. Therefore, the correct answer is (c).

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Complete question - Which expression is equal to 4.6?

a. 1.6 + (3 × 4) – 2 ÷ 2

b. 1.6 + 3 × 4 – 2 ÷ 2

c. [1.6 + (3 × 4)] – (2 ÷ 2)

d. (1.6 + 3) × (4 – 2) ÷ 2

Answer:

The distance between these parallel lines is 2 - (-7) = 9 units.

Answer:

Step-by-step explanation

π corresponds to 180 degrees.

so

180 : 8 = 22.5°

The area of the playground include the following: 900 square yards.

In Mathematics and Geometry, the area of a regular polygon can be calculated by using this formula:

Area = (n × s × a)/2

Where:

In Mathematics and Geometry, the area of a parallelogram can be calculated by using the following formula:

Area of a parallelogram, A = base area × height

Area of playground, A = 45 × 20

Area of a playground, A = 900 square yards.

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The sound level of the vocalizations of a blue whale is approximately 140.28 decibels.

The question asks us to find the sound level in decibels (db) of the vocalizations of a blue whale, given its sound intensity of 106.8 watts/meter2.

The formula for sound level in decibels is:

L = 10log(i/I0)

Where L is the sound level in decibels, i is the sound intensity in watts/meter2, and I0 is the smallest sound intensity that can be heard by the human ear (approximately 1x10⁻¹² watts/meter2).

Plugging in the given values, we get:

L = 10log(106.8/1x10⁻¹² )

Simplifying this expression, we get:

L = 10log(1.068x10¹⁴)

L = 10(14.028)

L = 140.28

Therefore, the sound level of the vocalizations of a blue whale is approximately 140.28 decibels.

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The initial number is approximately 7.33.

Let's call the initial number "x".

According to the problem, the first step is to write 2 to the right of the number: this gives us the number 10x + 2.

-The next step is to add 14 to this number, which gives us:

10x + 2 + 14 = 10x + 16

-Then we write 3 to the right of this number, giving:

100x + 16 + 3 = 100x + 19

-And finally, we add 52 to this number:

100x + 19 + 52 = 100x + 71

Dividing this final number by 60 gives a quotient that is 6 greater than the initial number and a remainder that is a two-digit number with both digits the same as the initial number.

-So we have the equation:

(100x + 71) ÷ 60 = x + 6 + 0.01x

-We want to solve for x, so we first multiply both sides by 60:

100x + 71 = 60(x + 6 + 0.01x)

-Simplifying the right-hand side:

100x + 71 = 60x + 360 + 0.6x

Combining like terms:

39.4x =289

Dividing both sides by 39.4:

x =7.33

Therefore, the initial number is approximately 7.33.

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The sample space for a child choosing one entrée and one side is A) BA, BF, CA, CF, PA, PF, SA, SF.So, the correct answer is A). Probability of a child choosing pizza or spaghetti with mixed vegetables is 2/15 or 0.1333 (rounded to four decimal places) or approximately 13.33%.

The sample space represents choose of one entrée and one side for his or her meal is BA, BF, CA, CF, PA, PF, SA, SF. So, the correct option is A).

After the addition of grilled cheese as an entrée choice and mixed vegetables as a side choice, there are now five entrée choices (B, C, P, S, G) and three side choices (A, F, MV). The total number of possible meal combinations is 5*3 = 15.

The number of meal combinations where the child chooses pizza or spaghetti with mixed vegetables is 2 (pizza with mixed vegetables and spaghetti with mixed vegetables). Therefore, the probability of choosing spaghetti or pizza with mixed vegetables for her or his meal is

P(pizza or spaghetti with mixed vegetables) = 2/15 = 0.1333 (rounded to four decimal places) or approximately 13.33%.

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--The given question is incomplete, the complete question is given

"At a restaurant, a children's meal gives a choice of four entrées: burger (B), chicken (C), pizza (P), or spaghetti (S), and two sides: apple (A) or fries (F).

Part A

Which sample space represents all the ways a child could choose one entrée and one side for his or her meal?

A) BA, BF, CA, CF, PA, PF, SA, SF

B) BA, CA, PA, SA

C) BF, CF, PF, SF

D) B, C, P, S, A, F

Part B

The restaurant decides to add another choice for the entrée and another choice for the side on the children's menu. The additional entrée choice is grilled cheese and the additional side choice is mixed vegetables. What is the probability that a child will choose pizza or spaghetti with mixed vegetables for his or her meal?"--

Answer:

-----------------------

F(x) is in the format of a quadratic function:

Hence it is a parabola.

The table represents a relation with two x-intercepts and two y-intercepts (points with the coordinate of 0).

We know that parabola can have maximum of one y-intercept, hence G(x) is not a parabola.

The matching answer choice is the first one.

Answer:

p = 38

Step-by-step explanation:

We Know

The 104° angle + (2p) angle must be equal to 180°.

Solve for the value of p.

Let's solve

104° + 2p = 180°

2p = 76°

p = 38

The measure of angle U in triangle UVW is approximately 28 degrees. This is found by using the inverse tangent function to solve for angle U given the lengths of two sides and the fact that angle W is a right angle.

To find the measure of ∠U in ΔUVW, we can use trigonometry. We know that sin(∠U) = opposite/hypotenuse, which is equal to UW/VW. Therefore, we can plug in the given values and solve for sin(∠U)

sin(∠U) = UW/VW = 2.2/4.7 = 0.4681

Next, we can use the inverse sine function (sin⁻¹) to find the measure of ∠U

∠U = sin⁻¹(0.4681) = 28.34 degrees (rounded to the nearest degree)

Therefore, the measure of ∠U in ΔUVW is approximately 28 degrees.

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None of the provided answer choices are correct, as the correct answer should be 41 lb.

To find the total weight of the box and the presents, you simply add the weights together:

Box weight: 14 lb
Present 1 weight: 15 lb
Present 2 weight: 12 lb

Total weight = 14 lb + 15 lb + 12 lb = 41 lb

None of the provided answer choices are correct, as the correct answer should be 41 lb.

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Answer:

Step-by-step explanation:

There are 26 letters in the alphabet and 10 digits that you can use (0,1,2,3,4,5,6,7,8,9)

As a result, we can find the number of combinations by doing the following:

26 x 26 x 10 x 10 x 10

since the first two symbols are alphabets and the last three are digits. After doing the math you get

26 x 26 x 10 x 10 x 10 = 676000 => You can make a total of 676,000 PIN codes

Answer:

(- 4, 4 )

Step-by-step explanation:

y = - 7x - 24 → (1)

y = - 2x - 4 → (2)

substitute y = - 2x - 4 into (1)

- 2x - 4 = - 7x - 24 ( add 7x to both sides )

5x - 4 = - 24 ( add 4 to both sides )

5x = - 20 ( divide both sides by 5 )

x = - 4

substitute x = - 4 into either of the 2 equations and evaluate for y

substituting into (1)

y = - 7(- 4) - 24 = 28 - 24 = 4

solution is (- 4, 4 )

Answer:

250+25d= P

Step-by-step explanation:

How to say it aloud: "$250 plus 25 times miles ran is equal to total amount earned"

250 is a fixed amount that is apart of the equation. In order to get a correct total at the end, $250 must be added to 25d.

25d stands for $25 times the amount of miles ran, which according to the word problem is represented by d. The reason we multiply 25 times d is because Marcus is getting $25 for every mile he runs. At the end of his run, we need to multiply $25 by those miles.

The reason everything equals P is because according to the word problem, P is the amount of money earned.

I hope that makes sense.

The total mass of the rod is 81622.5 kg. To find the total mass of the rod, you need to integrate the linear density function with respect to the length of the rod.

To find the total mass of the rod, we need to integrate the linear density function over the entire length of the rod.
Let's start by finding the linear density function at the end of the rod, which is a = 9:
p(9) = 3 + 2017 = 2020 kg/m
Now we can integrate the linear density function from a = 0 to a = 9 to find the total mass:
m = ∫₀⁹ p(a) da
m = ∫₀⁹ (3 + 2017a) da
m = [3a + 1008.5a²] from 0 to 9
m = (3(9) + 1008.5(9)²) - (3(0) + 1008.5(0)²)
m = 81622.5 kg
Therefore, the total mass of the rod is 81622.5 kg.

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Based on the information provided, Madeline and Ben invested $1500 for their son Peter's education on the day he was born at an interest rate of 6.7% compounded quarterly. Since Peter is now 19 years old and wants to go to college, we can calculate the current value of his education fund.

To do this, we can use the formula for compound interest:

A = P(1 + r/n)^(nt)

Where:
A = the final amount
P = the principal (initial investment)
r = the annual interest rate (as a decimal)
n = the number of times the interest is compounded per year
t = the time in years

In this case, we have:

P = $1500
r = 6.7% = 0.067 (as a decimal)
n = 4 (since the interest is compounded quarterly)
t = 19 (since Peter is now 19 years old)

So, the current value of Peter's education fund is:

A = $1500(1 + 0.067/4)^(4*19)
A = $1500(1.01675)^76
A = $1500(2.4826)
A = $3,723.90

Therefore, the current value of Peter's education fund is $3,723.90. This should help Madeline and Ben determine how much more they need to save for Peter's college expenses.

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The graphs are identified as follows

1. the domain is option G

2. the range is option E

3. the domain is option D

4. the range is option C

In coordinate geometry, the domain and range are concepts used to describe the set of possible inputs (x-values) and outputs (y-values) of a function, respectively.

The domain of a function is the set of all possible x-values for which the function is defined. In other words, it is the set of all values that can be plugged into the function and produce a meaningful output.

The range of a function is the set of all possible y-values that the function can take on as x varies over its domain. In other words, it is the set of all values that the function can output.

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The total surface area of the cone is 44π cm², where π represents the mathematical constant pi.

We have,

To find the total surface area of a cone, we need to calculate the lateral surface area (denoted by L) and the base area (denoted by B), and then sum them.

The lateral surface area of a cone is given by L = πrℓ, where r is the radius of the base and ℓ is the slant height.

The base area is given by B = πr², where r is the radius of the base.

Given the dimensions:

Radius of the base (r) = 4 cm

Slant height (ℓ) = 7 cm

We can calculate the lateral surface area as L = π(4)(7) = 28π cm².

The base area can be calculated as B = π(4^2) = 16π cm².

Now, to find the total surface area (SA), we sum the lateral surface area and the base area:

SA = L + B = 28π + 16π = 44π cm².

Therefore,

The total surface area of the cone is 44π cm², where π represents the mathematical constant pi.

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(a) Boris performed better on the aptitude test, since its z-score was higher.

(b) Callie performed better on the knowledge test.

(c) The z-score for the aptitude test was still higher than the z-score for the knowledge test, so Boris performed better on the aptitude test.

(a) To determine which test Boris performed better on, we need to compare his z-scores for the knowledge test and the aptitude test.

For the knowledge test, his z-score is calculated as:

z = (55 - 60) / 3 = -1.67

For the aptitude test, his z-score is:

z = (106 - 110) / 6.8 = -0.59

Since the z-score for the aptitude test is higher than the z-score for the knowledge test, Boris performed better on the aptitude test.

(b) To determine which test Callie performed better on, we need to compare her z-scores for the knowledge test and the aptitude test.

For the knowledge test, her z-score is:

z = (67 - 60) / 3 = 2.33

For the aptitude test, her z-score is:

z = (119 - 110) / 6.8 = 1.32

Since the z-score for the knowledge test is higher than the z-score for the aptitude test, Callie performed better on the knowledge test.

(c) Boris' z-score on the logic test (-0.43) is unrelated to his performance on the knowledge and aptitude tests, so it does not change the answer to which test he performed better on. The z-score for the aptitude test was still higher than the z-score for the knowledge test, so Boris performed better on the aptitude test.

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The balance when $3000 is invested at 4% rate for 20 years and compounded annually, semi-annually, quarterly, monthly, daily, and continuously are $6,372.76, $6,454.81, $6,506.71, $6,535.94, $6,546.49, and $6,549.18 respectively.

Compounding Frequency Balance after 20 Years

Annually $6,372.76

Semi-annually $6,454.81

Quarterly $6,506.71

Monthly $6,535.94

Daily $6,546.49

Continuous $6,549.18

Using the formula for compound interest:

A = P(1 + r/n)^(nt)

where A is the balance after t years, P is the principal (amount invested), r is the annual interest rate, n is the number of times the interest is compounded per year, and t is the number of years.

For p = $3000, r = 4%, t = 20 years, and the different compounding frequencies, we get:

Annually: A = $3000(1 + 0.04/1)^(1*20) = $6,372.76

Semi-annually: A = $3000(1 + 0.04/2)^(2*20) = $6,454.81

Quarterly: A = $3000(1 + 0.04/4)^(4*20) = $6,506.71

Monthly: A = $3000(1 + 0.04/12)^(12*20) = $6,535.94

Daily: A = $3000(1 + 0.04/365)^(365*20) = $6,546.49

Continuous: A = $3000e^(0.0420) = $6,549.18 (where e is the constant 2.71828...)

Therefore, the balance a when $3000 is invested at 4% rate for 20 years and compounded n times per year (where n is the different frequencies given) are as mentioned above.

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The toys approach each other at the distance of  630 cm.

To solve the problem, we can use the Pythagorean theorem.

Let the distance between the tugboat and the sail ship be d, and

let t be the time in seconds since they started moving.

Then we have:

Distance traveled by the tugboat (in cm) = 5t

Distance traveled by the sail ship (in cm) = 7t/sqrt(2)

Using the Pythagorean theorem, we have:

d² = (5t)² + (7t/(\sqrt(2)))²

d² = 25t² + 24.5t²

d² = 49.5t²

d = \sqrt(49.5)t

To find how closely the two toys approach each other, we need to find the minimum value of d.

This occurs when t is maximized, which happens when the toys are closest to each other.

The sail ship travels a distance of 8\sqrt(2) meters in the Northeast direction, which is equivalent to 800\sqrt(2) cm. Therefore, the time taken for the sail ship to travel this distance is:

t = (800\sqrt(2) cm) / (7 cm/(\sqrt(2))) = 200\sqrt(2) seconds

Substituting this value of t in the equation for d, we get:

d = \sqrt(49.5)(200\sqrt(2)) = 630 cm (corrected)

Therefore, the minimum distance between the two toys is 630 cm.

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The length of the base of the given triangle can be simplified as 2√2/5 feet, which is equivalent to √8/5 feet.

We are given that the area of the triangle is (2/25) * 252 square feet.

Let the length of the base be x. Then, the height of the triangle can be expressed as (2/5)x, since the base divides the triangle into two equal parts.

The area of the triangle is given by the formula A = (1/2)bh, where b is the length of the base and h is the height of the triangle.

Substituting the given values, we get:

(1/2)x(2/5)x = (2/25)*252

Simplifying this equation, we get:

(1/5)x²= 20.16

Multiplying both sides by 5, we get:

x² = 100.8

Taking the square root of both sides, we get:

x =√(100.8)

Simplifying this expression, we get:

Therefore, the length of the base is √(4.032) feet, which can be expressed as a fraction in simplest form as 2√(2)/5 feet.

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Answer:

[tex]20,000 \text{ kWh}[/tex]

Step-by-step explanation:

We can convert 68 million British Thermal Units (BTUs) to kilowatt-hours (kWh) using the given conversion ratio:

[tex]\dfrac{1 \text{ kWh}}{3400 \text{ BTUs}}[/tex]

Multiplying by the ratio:

[tex]68,000,000 \text{ BTUs} \cdot \dfrac{1 \text{ kWh}}{3,400 \text{ BTUs}}[/tex]

↓ canceling the BTU units

[tex]68,000,000\cdot \dfrac{1 \text{ kWh}}{3,400}[/tex]

↓ executing multiplication

[tex]\dfrac{68,000,000}{3,400} \text{ kWh}[/tex]

↓ rewriting as a decimal

[tex]\boxed{20,000 \text{ kWh}}[/tex]

A random sample that has 1000 college students in the United States is surveyed about how much money they spend on books per year, and the mean amount calculated is 1000 college students in the US. Option A is the correct answer.

The sample in this scenario refers to the group of college students who were surveyed about their book spending habits. In this case, the sample size is 1000 college students in the United States.

The purpose of this survey is to estimate the mean amount of money spent on books per year by college students in the US, using the sample mean as an estimate. It is important to note that the sample should be representative of the larger population of college students in the US.

Therefore, option A, "1000 college students in the US," is the correct answer. Option B, "all college students in the US," represents the population, not the sample. Options C and D are not relevant to the given scenario.

Learn more about the random sample at

https://brainly.com/question/31523301

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The question is -

A random sample of 1000 college students in the United States is surveyed about how much money they spend on books per year, and the mean amount is calculated. What is the sample?

a. 1000 college students in the US

b. all college students in the US

c. 1000 college students in CA

d. all college students in CA