I need help Plssplss

The volume of the cylinder is 3811.7 cubic units when the radius is 9 and the width is 15.

Volume = π × radius² × height

Substitute the given values:
Volume = π × (9)² × 15

Squaring the radius:
Volume = π × 81 × 15

Multiplying the values together:
Volume = π × 1215

Calculating the volume using the approximate value of π (3.14):
Volume ≈ 3.14 × 1215

Calculating the final volume:
Volume ≈ 3811.7 cubic units

So, the volume of the cylinder with a radius of 9 and a height of 15 is approximately 3811.7 cubic units.

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Answer:

f(-2) = 9

Step-by-step explanation:

f(x) = -3x + 3                       Solve for f(-2)

f(-2) = -3(-2) + 3

f(-2) = 6 + 3

f(-2) = 9

None of the bills have an experimental probability of 3, as all probabilities are between 0 and 1.

Based on the table, the experimental probability for each bill being drawn from the bag next can be calculated by dividing the frequency of each bill by the total number of draws (100). Using this formula, we can calculate the experimental probabilities for each bill:

1. For the $1 bill: Experimental probability = [tex]\frac{(Frequency of  $1 bill)}{Total draws} = \frac{8}{100} = 0.28[/tex]
2. For the $10 bill: Experimental probability =[tex]\frac{(Frequency of  $10 bill)}{Total draws} = \frac{56}{100} = 0.56[/tex]
3. For the $20 bill: Experimental probability =[tex]\frac{(Frequency of  $20 bill)}{Total draws} = \frac{2}{100} = 0.02[/tex]

None of the bills have an experimental probability of 3, as all probabilities are between 0 and 1.

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The correct answer is option 2. Yes, the mean of the sample proportions is 0.6, which is the same as the population proportion.

To determine if the sample proportion is an unbiased estimator, we need to check if the mean of the sample proportions equals the population proportion. In this case, the population proportion of officers who are younger than 18 is given as 0.6. The sample proportions for all possible samples of size 2 are calculated and given in the table.
To calculate the mean of the sample proportions, we add up all the proportions in the table and divide by the total number of samples, which is 9.
Mean of sample proportions = (0 + 0.5 + 0.5 + 0.5 + 0.5 + 0.5 + 1 + 1 + 1) / 9 = 0.6
Since the mean of the sample proportions equals the population proportion, we can say that the sample proportion is an unbiased estimator.

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The instant when the radar gun is used, the rate at which the distance between the two cars is changing is g'(t) = 7968t + 368/5 kilometers per hour.

Let's break down the problem. We have two cars, one traveling south at 112 km/h and another traveling west at 96 km/h. The police car is stationed at an intersection and the two cars are at different points relative to the intersection. The first car is 4/5 kilometer north of the intersection while the second car is 2/5 kilometer east of the intersection.

Let's call this distance "d". Using the Pythagorean theorem, we can write:

d² = (4/5)² + (2/5)² d² = 16/25 + 4/25 d² = 20/25 d = sqrt(20)/5 d = 2sqrt(5)/5 kilometers

Now, we need to find the rate at which the distance between the two cars is changing. This is equivalent to finding the derivative of the distance with respect to time. Let's call this rate "r".

To find "r", we need to use the chain rule. The distance between the two cars is a function of time, so we can write:

d = f(t)

where t is time. We can then write:

r = d'(t) = f'(t)

where d'(t) and f'(t) denote the derivatives of d and f with respect to time, respectively.

To find f'(t), we need to express d in terms of t. We know that the first car is traveling at a constant speed of 112 km/h due south. Let's call the position of the first car "x" and the time "t". Then we have:

x = -112t

The negative sign indicates that the car is moving south. Similarly, we can express the position of the second car in terms of time. Let's call the position of the second car "y". Then we have:

y = 96t

The positive sign indicates that the car is moving west.

Now, we can use these expressions to find the distance between the two cars as a function of time. Let's call this function "g(t)". Then we have:

g(t) = √((x + 4/5)² + (y - 2/5)²) g(t) = √((-112t + 4/5)² + (96t - 2/5)²)

To find g'(t), we need to use the chain rule. We have:

g'(t) = (1/2)(x + 4/5)'(x + 4/5)'' + (y - 2/5)'x(y - 2/5)''

where the primes denote derivatives with respect to time. We can simplify this expression by noting that x' = -112 and y' = 96. We also have x'' = y'' = 0, since the speeds of the two cars are constant.

Substituting these values, we get:

g'(t) = -112x(-112t + 4/5)/√((-112t + 4/5)² + (96t - 2/5)²) + 96x(96t - 2/5)/√((-112t + 4/5)² + (96t - 2/5)²)

Simplifying this expression, we get:

g'(t) = (-112x(-112t + 4/5) + 96x(96t - 2/5))/√((-112t + 4/5)² + (96t - 2/5)²)

We can further simplify this expression by multiplying out the terms in the numerator:

g'(t) = (-12544t + 560/5 + 9216t - 192/5)/√((-112t + 4/5)² + (96t - 2/5)²)

g'(t) = (7968t + 368/5)/√((-112t + 4/5)² + (96t - 2/5)²)

g'(t) = 7968t + 368/5

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Complete Question:

A car is traveling at 112 km/h due south at a point 4/5 kilometer north of an intersection_ police, the car Is traveling at 96 km/h due west to at point 2/5 kilometer due cust of the same intersection. At that instant; the radar in the police car measures the rate at which the distance between the two cars [ changing: What does the radar gun register?

The definite integral

[tex]-e^(2z)/u + 16e^z/u - 64ln(u)/u + C[/tex]

To evaluate this definite integral, we need to find the antiderivative of the integrand and evaluate it at the limits of

integration.

Let's start by using u-substitution:

Let [tex]u = e^z+8z[/tex]

Then [tex]du/dz = e^z+8[/tex]

And [tex]dz = 1/e^z+8 du[/tex]

Substituting this into the integral, we get:

[tex]∫(e^z) + 8/ (e^z+8z)^2 dz[/tex]

= [tex]∫(1/u^2)(e^z+8)^2 du[/tex]

= [tex]∫(1/u^2)(e^(2z)+16e^z+64) du[/tex]

= [tex]-e^(2z)/u + 16e^z/u - 64ln(u)/u + C[/tex]

Now we need to evaluate this antiderivative at the limits of integration.

Let's assume the limits are a and b:

= [tex][-e^(2b)/(e^b+8b) + 16e^b/(e^b+8b) - 64ln(e^b+8b)/(e^b+8b)] - [-e^(2a)/(e^a+8a) + 16e^a/(e^a+8a) - 64ln(e^a+8a)/(e^a+8a)][/tex]

Simplifying this expression is not easy, but it can be done with some algebraic manipulation.

Therefore, The definite integral

[tex]-e^(2z)/u + 16e^z/u - 64ln(u)/u + C[/tex]

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Gail's observations about the box is correct. According to the question the edge of a cube-shaped box is 1 yard.

Now convert the edge length to feet as : 1 yard = 3 feet.

On checking the observations:

1.  According to Janae the area of each face is 9 square feet. Calculating the surface area of one face of the cube is given by:

Area = (edge length)² = (3 feet)² = 9 square feet.

Now, Total surface area = 6*9square feet= 54 square feet.

Hence Observations of Janae is not correct.

2. According to Archie perimeter of each face of the box is 3 feet. Calculating the perimeter of each face of the cube is given by:

Perimeter= 4 × (edge length)=4×1 yard= 4×3feet=12 feet

Hence Archie observation is not correct also.

3. According to Gail the volume of the box is 1 cubic yard.

The volume of a cube is given by:

volume= (edge length)³ = (1 yard)³ = 1 cubic yard.

Therefore Gail's observation is correct.

From all the above observations it can be concluded that only Gail's observation is correct.

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The carbon dioxide level in the atmosphere is modeled using two possible derivative functions. Using Model I, the level in 2050 is approximately 426.25 ppm, and using Model II, it is approximately 522.73 ppm.

Using Model I

We need to integrate the derivative function C'(t) = 0.5 + 0.025t to get C(t).

∫C'(t) dt = ∫0.5 + 0.025t dt

C(t) = 0.5t + (0.025/2)t^2 + C

Using the initial condition that C(0) = 370, we get

370 = 0 + 0 + C

C = 370

So, C(t) = 0.5t + (0.025/2)t^2 + 370

To find the carbon dioxide level in 2050 using Model I

C(50) = 0.5(50) + (0.025/2)(50)^2 + 370

C(50) = 25 + 31.25 + 370

C(50) = 426.25 ppm

Using Model II

We need to integrate the derivative function C'(t) = 0.5e^(0.025t) to get C(t).

∫C'(t) dt = ∫0.5e^(0.025t) dt

C(t) = (20e^(0.025t))/ln(10) + C

Using the initial condition that C(0) = 370, we get

370 = (20e^(0))/ln(10) + C

C = 370 - (20/ln(10))

So, C(t) = (20e^(0.025t))/ln(10) + (370 - (20/ln(10)))

To find the carbon dioxide level in 2050 using Model II

C(50) = (20e^(0.025(50)))/ln(10) + (370 - (20/ln(10)))

C(50) = 522.73 ppm (rounded to two decimal places)

Therefore, the carbon dioxide level in 2050 is approximately 426.25 ppm using Model I, and approximately 522.73 ppm using Model II.

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(a) First, we need to find the derivative of the cost function, C'(x), with respect to x.

The given function is: C(x) = -10x^2 + 500x + 110

To find the derivative, we will apply the power rule:

C'(x) = d/dx (-10x^2) + d/dx (500x) + d/dx (110)

For each term: d/dx (-10x^2) = -20x d/dx (500x) = 500 d/dx (110) = 0 So, C'(x) = -20x + 500

(b) Now, we need to find the rate of change of the total cost when the level of production is 7 surfboards a day.

To do this, we will substitute x=7 into the derivative function C'(x): C'(7) = -20(7) + 500 C'(7) = -140 + 500 C'(7) = 360

The rate of change of the total cost when the level of production is 7 surfboards a day is $360 per surfboard.

Your answer: a) C'(x) = -20x + 500 b) $360 per surfboard

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Bill sold 140 bottles of cherry soda and 70 bottles of grape soda.

Let's assume that x is the number of bottles of cherry soda sold and y is the number of bottles of grape soda sold. We can set up a system of equations to represent the given information:

x + y = 210 (equation 1: the total number of bottles sold is 210)

1.15x + 0.99y = 230.30 (equation 2: the total cost of the sodas is $230.30)

We can use the first equation to solve for y in terms of x:

y = 210 - x

Substituting this expression for y into the second equation, we get:

1.15x + 0.99(210 - x) = 230.30

Simplifying and solving for x, we get:

1.15x + 207.9 - 0.99x = 230.30

0.16x = 22.4

x = 140

So Bill sold 140 bottles of cherry soda. Substituting this value into equation 1, we get:

140 + y = 210

y = 70

Therefore, Bill sold 140 bottles of cherry soda and 70 bottles of grape soda.

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To differentiate x^6y^9 with respect to x, we will use the product rule. The product rule states that the derivative of a product of two functions is the derivative of the first function multiplied with the second function, plus the first function multiplied with the derivative of the second function.

Step 1: Identify the functions
Function 1 (u): x^6
Function 2 (v): y^9

Step 2: Find the derivatives
u' (du/dx): Differentiate x^6 with respect to x, which gives 6x^5
v' (dv/dx): Differentiate y^9 with respect to x, which gives 9y^8 * (dy/dx) = 9y^8D (since D = dy/dx)

Step 3: Apply the product rule
d/dx (x^6y^9) = u'v + uv'
= (6x^5)(y^9) + (x^6)(9y^8D)
= 6x^5y^9 + 9x^6y^8D

So, the derivative of x^6y^9 with respect to x is 6x^5y^9 + 9x^6y^8D.

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Based on the given situation we can conclude that the sedan retains its value better than the pickup truck over time.The functions S(t) and P(t) represent the values of the sedan and pickup truck, respectively, as a function of the number of years t after their purchase.

The coefficient 24,400 in the function S(t) represents the initial value of the sedan, which is the value of the car at t=0. The base 0.82 represents the decay rate or the percentage decrease in the value of the sedan each year. Similarly, in the function P(t), the coefficient 35,900 represents the initial value of the pickup truck and the base 0.71 represents the decay rate of the value of the pickup truck.

Since the base of the sedan's value decay is 0.82, it indicates that the value of the sedan decreases by 18% each year. Whereas the base of the pickup truck's value decay is 0.71, indicating that the value of the pickup truck decreases by 29% each year. Therefore, we can observe that the value of the pickup truck depreciates faster than the sedan. After two years, the value of the sedan would be approximately $16,650, and the value of the pickup truck would be approximately $14,161. After five years, the value of the sedan would be approximately $9,237, and the value of the pickup truck would be approximately $6,155.

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The investor invested $500,000 in Swan Peak and $600,000 in Riverside Community.

Let's denote the amount invested in Swan Peak as x and the amount invested in Riverside Community as y.

According to the given information:

1. The return on investment in Swan Peak was a 110% increase, which means the total return was 100% + 110% = 210% of the initial investment.

2. The return on investment in Riverside Community was 50% over the initial investment, which means the total return was 100% + 50% = 150% of the initial investment.

We are also given that the investor earned $1 million in profits.

Based on the above information, we can set up the following equations:

1.1 million = 2.1x + 1.5y  (equation 1)    [This equation represents the total profits earned by the investor.]

x + y = 1.1 million  (equation 2)    [This equation represents the total amount invested.]

To solve these equations, we can use substitution or elimination method. Let's use the elimination method:

Multiply equation 2 by 2.1 to make the coefficients of x in both equations equal:

2.1x + 2.1y = 2.31 million   (equation 3)

Now, subtract equation 1 from equation 3 to eliminate x:

(2.1x + 2.1y) - (2.1x + 1.5y) = 2.31 million - 1.1 million

0.6y = 1.21 million

Divide both sides by 0.6:

y = 2.01 million / 0.6

y ≈ 3.35 million

Substitute the value of y into equation 2:

x + 3.35 million = 1.1 million

x ≈ 1.1 million - 3.35 million

x ≈ -2.25 million

Since the amount invested cannot be negative, we discard the negative value.

Therefore, the investor invested approximately $500,000 in Swan Peak (x) and approximately $600,000 in Riverside Community (y).

Hence, the investor invested $500,000 in Swan Peak and $600,000 in Riverside Community.

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Answer:

b+24

Step-by-step explanation:

the sum of a number represented by variable b

-- b+

and 24

-- b+24

Answer: b + 24

Step-by-step explanation:

The sum of .. and ➜ addition between two values

a number b ➜ b (represented by a variable)

24 ➜ the number 24

         The sum of a number b and 24 ➜ b + 24

The interval where y increases for the function f(x) = (4x² - 1)/(x² + 1) is (-∞, -0.5) U (0.5, ∞) is 0.5-(-∞) = ∞.

To find the intervals where the function f(x) = (4x² - 1)/(x² + 1) increases, we need to find its derivative and determine its sign. The derivative of f(x) can be found using the quotient rule:

f'(x) = [(8x)(x² + 1) - (4x² - 1)(2x)]/(x² + 1)²

Simplifying this expression, we get:

f'(x) = (12x - 4x³)/(x² + 1)²

To find the critical points, we need to solve the equation f'(x) = 0:

12x - 4x³ = 0

4x(3 - x²) = 0

This gives us the critical points x = 0 and x = ±√3. We can now test the intervals between these critical points to determine the sign of f'(x) in each interval.

Testing x < -√3, we choose x = -4, and we get f'(-4) = (-224)/(17²) < 0. Therefore, f(x) is decreasing on this interval.

Testing -√3 < x < 0, we choose x = -1, and we get f'(-1) = (16)/(2²) > 0. Therefore, f(x) is increasing on this interval.

Testing 0 < x < √3, we choose x = 1, and we get f'(1) = (16)/(2²) > 0. Therefore, f(x) is increasing on this interval.

Testing x > √3, we choose x = 4, and we get f'(4) = (-224)/(17²) < 0. Therefore, f(x) is decreasing on this interval.

Hence, the interval where f(x) increases is (-∞, -0.5) U (0.5, ∞). Therefore, the answer is 0.5 - (-∞) = ∞.

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The correct answer is 9% interest rate and 25 years.

To find the correct answer, we can use the mortgage payment formula:

M = P * (r(1 + r)^n) / ((1 + r)^n - 1)

Where:
M = monthly mortgage payment ($629.81)
P = principal loan amount ($70,000)
r = monthly interest rate (annual interest rate / 12)
n = total number of payments (years * 12)

We can test each option to see which one fits the given mortgage payment.

1) 9%, 20 years:
r = 0.09 / 12 = 0.0075
n = 20 * 12 = 240

M = 70000 * (0.0075(1 + 0.0075)^240) / ((1 + 0.0075)^240 - 1)
M ≈ $629.29 (close but not exact)

2) 9%, 25 years:
n = 25 * 12 = 300

M = 70000 * (0.0075(1 + 0.0075)^300) / ((1 + 0.0075)^300 - 1)
M ≈ $629.81 (matches the given mortgage payment)

Based on our calculations, the correct answer is 9% interest rate and 25 years.

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The most appropriate conclusion that can be made when the null hypothesis is rejected for the chi-square test of independence is: There is a significant association between fear of crime and one's perception of their neighborhood as a high crime area or not.

If the null hypothesis is rejected in a chi-square test of independence, it means that there is a significant association between the two variables being studied. In this case, the fear of crime is dependent on one's perception of whether their neighborhood is a high crime area or not.

Therefore, the most appropriate conclusion that can be made is that there is a significant relationship between the two variables, and one's perception of their neighborhood being a high crime area or not is a predictor of fear of crime. However, the chi-square test of independence does not determine causality, so it is not possible to conclude which variable is causing the other. Further research would be required to determine the direction and nature of the relationship between the two variables.

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The contribution margin for braised greens is $2.68.

The contribution margin is a financial metric that helps businesses determine the profitability of a product or service. It represents the amount of revenue that is left over after deducting the variable costs of producing that product or service.

In this case, the ingredients for the braised greens cost $1.32, and the selling price is $4, so the contribution margin would be $2.68 ($4 - $1.32 = $2.68).

This means that for every sale of the braised greens, the business earns $2.68 towards covering fixed costs and generating profit. By calculating the contribution margin, businesses can determine the pricing strategy that is necessary to achieve their desired profit margins while remaining competitive in the market.

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Answer: Pairs (0, 14) and (10, 0

Step-by-step explanation:

The correlation between the number of points scored by the basketball team and the weeks of the season is likely negative.

However, without seeing the actual data, it is difficult to determine the exact correlation. As for the coach's statement, it could be either correct or incorrect depending on the actual data. Based on the given information, the basketball coach's observation suggests a negative correlation between the number of weeks into the season and the points scored by his team. Without the actual data, it is impossible to determine if his observation is correct or incorrect.

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The temperature at 11:00 A.M. yesterday was 78°F.

To find the temperature at 11:00 A.M., we need to subtract 9 from the temperature at 4:00 P.M. because the temperature rose 9 degrees between those times. So, we can use the following equation:

Temperature at 11:00 A.M. = Temperature at 4:00 P.M. - 9

We know that the temperature at 4:00 P.M. was 87°F, so we can substitute that into the equation and solve for the temperature at 11:00 A.M.:

Temperature at 11:00 A.M. = 87 - 9

Temperature at 11:00 A.M. = 78°F

Therefore, the temperature at 11:00 A.M. yesterday was 78°F.

It's important to remember that when solving word problems like this, we need to pay close attention to the details and make sure we understand what the question is asking us to find. In this case, we needed to use the information given about the temperature rising 9 degrees between 11:00 A.M. and 4:00 P.M. to find the temperature at 11:00 A.M. By using the equation provided and substituting in the known values, we were able to solve for the unknown temperature at 11:00 A.M.

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Proportionately, if 8 cm represents​ 10%, the length of a line segment that is​ 100% is 80 cm.

Proportion is the ratio of two quantities equated to each other.

Proportion also represents the portion or part of a whole.

Proportions can be represented using decimals, fractions, or percentages, like ratios.

The percentage of 8 cm length = 10%

The whole length = 100%

Proportionately, 100% = 80 cm (8 ÷ 10%) or (8 x 100 ÷ 10)

Thus, we can conclude that 100% of the line segment will be 80 cm if 8 cm is 10%.

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If 8 cm represents​ 10%, what is the length of a line segment that is​ 100%? Explain.

The 95% CI for the genuine proportion of this bank's checking account customers who also have savings accounts is (0.3666, 0.4976).

To construct a 95% confidence interval for the true proportion of checking account customers who also have savings accounts, we can use the following formula:

CI = p ± z*√(p*(1-p)/n)

where:

We are given that the sample size is n = 243 and that 105 of the customers had both checking and savings accounts. Therefore, the sample proportion is:

p = 105/243 = 0.4321

The critical value z for a 95% confidence interval is approximately 1.96 (obtained from a standard normal distribution table or calculator).

We get the following results when we plug these values into the formula:

CI = 0.4321 ± 1.96*√(0.4321*(1-0.4321)/243)

CI = 0.4321 ± 0.0655

CI = (0.3666, 0.4976)

Therefore, we can say with 95% confidence that the true proportion of checking account customers who also have savings accounts at this bank is between 0.3666 and 0.4976.

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Polar coordinates for rectangular coordinates if x<0: r=√(x²+y²) and θ=tan⁻¹(y/x)+π if y≥0 or θ=tan⁻¹(y/x)−π if y<0, For x≥0: r=√(x²+y²) and θ=tan⁻¹(y/x) if y≥0 or θ=tan⁻¹(y/x)+2π if y<0.

The polar coordinates of a point with rectangular coordinates (x,y) depend on the sign of x.

If x<0, the polar coordinates are (r,θ) where r≥0 and −π/2≤θ<3π/2. If x≥0, the polar coordinates are (r,θ) where r≥0 and −π/2≤θ<3π/2.

If x<0, t

hen r=√(x²+y²) and

θ=tan⁻¹(y/x)+π if y≥0

or θ=tan⁻¹(y/x)−π if y<0.

The value of r is the distance from the origin to the point and θ is the angle between the positive x-axis and the line segment from the origin to the point.

If x≥0, then r=√(x²+y²) and θ=tan⁻¹(y/x) if y≥0 or θ=tan⁻¹(y/x)+2π if y<0.

In this case, θ is the angle between the positive x-axis and the line segment from the origin to the point, measured counterclockwise.

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The magnitude and direction of the vector u = <-4, 7> are |u| ≈ √65 and θ ≈ 119.74°.

To find the magnitude and direction of the vector u = <-4, 7>, we will use the following steps:

1. Calculate the magnitude using the Pythagorean theorem.
2. Calculate the direction using the arctangent function.

Step 1: Calculate the magnitude.
Magnitude (|u|) = √((-4)^2 + (7)^2) = √(16 + 49) = √65

Step 2: Calculate the direction (angle θ).
θ = arctan(opposite/adjacent) = arctan(7/-4) ≈ -60.26° (in degrees)
Since the vector is in the second quadrant, we need to add 180°.
θ = -60.26° + 180° ≈ 119.74°

So, the magnitude and direction of the vector u = <-4, 7> are |u| ≈ √65 and θ ≈ 119.74°.

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r2 = 0.523, which means that approximately 52.3% of the variance in the difference scores can be accounted for by the reduction in mental alertness after consuming tryptophan.

a. To test whether there is a significant reduction in mental alertness after consuming tryptophan versus before, we can use a paired samples t-test. The null hypothesis is that there is no difference in mental alertness scores before and after the meal, and the alternative hypothesis is that the scores are lower after the meal:

H0: μd = 0 (no difference)

Ha: μd < 0 (lower scores after the meal)

Here, μd is the mean difference score in mental alertness before and after the meal. We will use a one-tailed test with α = .05, since we are only interested in the possibility of lower scores after the meal.

The t-statistic for a paired samples t-test is calculated as:

t = (Md - μd) / (sd / sqrt(n))

Where Md is the mean difference score, μd is the hypothesized mean difference (in this case, 0), sd is the standard deviation of the difference scores, and n is the sample size.

We are given that Md = 14, and the standard deviation of the difference scores (sd) is:

sd = sqrt(SSd / (n - 1)) = sqrt(1152 / 8) = 12

Substituting these values, we get:

t = (14 - 0) / (12 / sqrt(9)) = 3.5

Using a one-tailed t-distribution table with 8 degrees of freedom and α = .05, the critical value is -1.86. Since our calculated t-value (3.5) is greater than the critical value, we reject the null hypothesis and conclude that there is a significant reduction in mental alertness after consuming tryptophan versus before.

b. To compute r2 to measure the size of the effect, we can use the formula:

r2 = t2 / (t2 + df)

Where t is the calculated t-value for the test, and df is the degrees of freedom, which is n-1 in this case.

Substituting the values , we get:

r2 = (3.5)2 / ((3.5)2 + 8) = 0.523

Therefore, r2 = 0.523, which means that approximately 52.3% of the variance in the difference scores can be accounted for by the reduction in mental alertness after consuming tryptophan.

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Conducting a survey among the students would be the best way to determine the most popular type of vending machine.

In order to accurately determine the most popular type of vending machine, it is important to gather data from the intended audience - the students. By conducting a survey, the administrator can gather information on the types of snacks and drinks that the students prefer, as well as their pricing preferences.

This will allow the administrator to make an informed decision on which type of vending machine will be most popular and profitable for the school.

Additionally, by involving the students in the decision-making process, they may feel more invested in the vending machines and be more likely to use them, ultimately leading to a successful vending program.

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Answer:

x=7

Step-by-step explanation:

Because all the bases are the same you can ignore the 8's.

Instead solve for 15=x+8

in which you would subtract the 8 to the left side, and 15-8=7

Answer:

Obtuse

Step-by-step explanation:

Right angles are 90° so incorrect

Acute angles are less than 90°, also incorrect

Obtuse angles are between 90 and 180. And this is the range which 137 is found

So angle S is obtuse

Answer:

B) Obtuse

Step-by-step explanation:

Let's look at the definitions for each answer choice:

Acute: An acute angle is an angle that measures less than 90°.

Obtuse: An obtuse angle is an angle that measures more than 90°.

Right: A right angle is an angle that measures exactly 90°.

Given that Angle S is 137°, we can classify this angle as an obtuse angle, as 137>90.

Hope this helps! :)