A study published in 2010 showed that city dwellers have a higher risk of developing anxiety disorders and a higher risk of developing mood disorders than those who live in the country. A follow-up study published in 2011 used brain scans of city dwellers and country dwellers as they took a difficult math test.1 To increase the stress of the participants, those conducting the study tried to humiliate the participants by telling them how poorly they were doing on the test. The brain scans showed very different levels of activity in stress centers of the brain, with the urban dwellers having greater brain activity than rural dwellers in areas that react to stress.

Required:

a. Is the 2010 study an experiment or an observational study?
i. Experiment
ii. Observational study

b. Can we conclude from the 2010 study that living in a city increases a person's likelihood of developing an anxiety disorder or mood disorder?
i. Yes
ii. No

c. Is the 2011 study an experiment or an observational study?
i. Experiment
ii. Observational study

d. Can we conclude from the 2011 study that living in a city increases activity in stress centers of the brain when a person is under stress?
i. Yes
ii. No

Answer:

a= 0

b= [tex]-\frac{\sqrt{42} }{12}[/tex]

Step-by-step explanation:

We can rewrite the expression to be:

[tex]\frac{i\sqrt{7} }{i^{2}\sqrt{24} }[/tex]

We then can cancel out the i and we get

[tex]\frac{\sqrt{7} }{\sqrt{24} i}[/tex]

Can be rewritten as

[tex]\frac{\sqrt{7} }{2\sqrt{6} i}[/tex]

We then rationalize and get

[tex]-\frac{\sqrt{42} }{12} i[/tex]

Answer:

9.9

Step-by-step explanation:

remember your distribution rules.

x/3.3=3 make sure x is by itself. so take 3*3.3

When you have x divided by a number equaling a number take the number it equals to and multiply by the number that x is being divided by.

3=x/3.3

move 3.3 by multiplying it by 3 which gives you 9.9.

The solution of x in equation 3 = x / 3.3 is,

⇒ x = 9.9

We have to given that;

Expression is,

⇒3 = x / 3.3

Now, We can simplify the equation for x as;

⇒ 3 = x / 3.3

Multiply by 3.3 both side,

⇒ 3 × 3.3 = x

⇒ 9.9 = x

⇒ x = 9.9

Thus, Solution is,

⇒ x = 9.9

Learn more about the equation visit:

brainly.com/question/28871326

#SPJ6

Answer:

Population = 34.27336

Step-by-step explanation:

Given:

Population function (t) = 34(1.00804)^t

Number of year = 2000

Find:

Number of citizen in year 2000

Computation:

We know that, base year is 2000

So, t = 1

Population function (t) = 34(1.00804)^t

Population function (1) = 34(1.00804)^1

Population = 34(1.00804)

Population = 34.27336

Therefore, Population is 34.273636 million

Answer:

x = -7.33        OR         x = [tex]\frac{-22}{3}[/tex]

y = 13

Step-by-step explanation:

→You can use the substitution method. First, make y by itself in (-2 + 2y = 24):

-2 + 2y = 24

2y = 26

y = 13

→Then, plug in 13 for y into the other equation:

3x + 2y = 4

3x + 2(13) = 4

3x + 26 = 4

3x = -22

x = -7.33        OR         x = [tex]\frac{-22}{3}[/tex]

Answer:

[tex] E(100 Y^2) =100 E(Y^2)[/tex]

And we have that :

[tex] E(Y^2) =\sum_{i=1}^n X^2_i P(X_i)[/tex]

And replacing we got:

[tex] E(Y^2) =0^2 *0.6 + 1^2 *0.25 +2^2*0.10 +3^2 *0.05 = 1.1[/tex]

And finally we have:

[tex] E(100 Y^2) =100 *1.1 = 110[/tex]

Step-by-step explanation:

For this case we have the following probability masss function given:

Y         0           1              2             3

p(Y)    0.6        0.25      0.10         0.05

And we can define the surcharge with this expression [tex] 100Y^2[/tex]

We want to find the expected value for the last expression and we can do it on this way:

[tex] E(100 Y^2) =100 E(Y^2)[/tex]

And we have that :

[tex] E(Y^2) =\sum_{i=1}^n X^2_i P(X_i)[/tex]

And replacing we got:

[tex] E(Y^2) =0^2 *0.6 + 1^2 *0.25 +2^2*0.10 +3^2 *0.05 = 1.1[/tex]

And finally we have:

[tex] E(100 Y^2) =100 *1.1 = 110[/tex]

Answer:

D: 17 times

Step-by-step explanation:

Volume of tank = 36×13×24

= 11,232 cubic inches

Now

Bucket = 693 cubic inches

Number of time Valeria will use the bucket = 11232/693

= 16.2

≈ 17

Answer:

2.964

Step-by-step explanation:

Answer:

x = 22

Step-by-step explanation:

The exterior angle of a triangle is equal to the sum of the interior angles

6x+1 = 79+ 2x+10

Combine like terms

6x+1 = 2x+89

Subtract 2x from each side

4x+1 = 89

Subtract 1 from each side

4x = 88

Divide by 4

4x/4 = 88/4

x = 22

Answer:

The answer is

Step-by-step explanation:

We can cross out A. So it has to be either B, C, or D.

Answer:

work is shown and pictured

The factor of the equation x² - 9x + 14 is,

⇒ (x - 2)

Mathematical expression is defined as the collection of the numbers variables and functions by using operations like addition, subtraction, multiplication, and division.

Given that;

The equation is,

⇒ x² - 9x + 14

Now, We can find the factor of the expression as;

⇒ x² - 9x + 14

⇒ x² - 7x - 2x + 14

⇒ x (x - 7) - 2 (x - 7)

⇒ (x - 7) (x - 2)

Thus, The factor of the equation x² - 9x + 14 is,

⇒ (x - 2)

Learn more about the mathematical expression visit:

brainly.com/question/1859113

#SPJ7

Answer:

(A)Decay

(b)0.8

(c)First Term

(d)[tex]f(t)=2000(0.8)^t[/tex]

(e)$819.20

Step-by-step explanation:

The exponential function for modelling growth or decay is given as:

[tex]A(t)=A_o(1\pm r)^t[/tex],

Where:

Plus indicates growth and minus indicates decay.

[tex]A_o$ is the Initial Value\\r is the growth/decay rate\\t is the time period[/tex]

For a powerful computer that was purchased for $2000, but loses 20% of its value each year.

(a)Since it loses value, it is a decay.

(b)Multiplier

Its value decays by 20%.

Therefore, our multiplier(1-r) =(1-20&)=1-0.2

Multiplier =0.8

(c)$2000 is our First term (or Initial Value [tex]A_o[/tex])

(d)The function for this problem is therefore:

[tex]f(t)=f_o(1- r)^t\\f(t)=2000(1- 0.2)^t\\\\f(t)=2000(0.8)^t[/tex]

(e)Since we require the worth of the computer after 4 years,

t=4 years

[tex]f(4)=2000(0.8)^4\\f(4)=\$819.20[/tex]

Answer:

7/3

Step-by-step explanation:

Write this symbolically as:

  7/9

 -------

   1/3

Invert the denominator fraction and then multiply:

(7/9)(3/1)

Reducing this, we get 7/3

Answer:

the answer as a mixed number is 2 and 1/3  (2 1/3)

and as a normal fraction its 7/3

Answer:

Coefficient of variation (weight) = 15%

Coefficient of variation (volume) = 25%

Step-by-step explanation:

Let's begin by listing out the given information:

Population = 200, Average weight = 26 lb,

standard deviation (weight) = 3.9 lb,

Average volume = 8.8 ft³,

standard deviation (volume) = 2.2 ft³

Based on the data given, the manager will have to make a deduction by comparing the relative scatter of both variables due to the different units of measuring weight (pounds) and volume (cubic feet).

To compare the variation of the weight and volume, we use the coefficient of variation given by the formula:

Coefficient of Variation = (Standard deviation ÷ Mean) * 100%

⇒ [tex]C_{v}[/tex] = (σ ÷ μ) * 100%

For weight

σ = 3.9 lb, μ = 26 lb

[tex]C_{v}[/tex] (weight) = (3.9 ÷ 26.0) * 100% = 15%

[tex]C_{v}[/tex] (weight) = 15%

For volume

σ = 2.2 ft³, μ = 8.8 ft³

[tex]C_{v}[/tex] (volume) = (2.2 ÷ 8.8) * 100% = 25%

[tex]C_{v}[/tex] (volume) = 25%

∴ the relative variation of the volume of the package is greater than that of the weight of the package

Answer:

A. 20.5

Step-by-step explanation:

We can use the Pythagorean theorem to solve this equation for the missing side length, X.

a^2 + b^2 = c^2

We have a and b, we just need c, the hypotenuse.

14^2 + 15^2 = c^2

196 + 225 = c^2

421 = c^2

Now, we will square both sides:

The answer is about 20.5

Answer:

L = 3/4

Option A. The Root Test says that the series converges absolutely.

Step-by-step explanation:

By using the root test equation given in the question. L = 3/4

Since L < 1, the series converges absolutely.

For clarity of expression, the detailed calculation is contained in the attached file. Check the file attached for the complete calculation to this question.

Answer:

NO

Step-by-step explanation:

The objective of this surveys is to determine if the two surveys will reach a similar conclusion.

From the data given, we have  two test surveys here:

The survey is to measure the effect of an advertising campaign for a certain brand of detergent.

Now in the first survey; interviewers ask house- wives whether they use that brand of detergent and in the second survey  the interviewers ask to see what detergent is being used.

Let assume that the brand name of the detergent is KLIN ;

From this disparities of statement ; we anticipate that they will reach different conclusion. This is because; from the first survey people will either respond to the fact that they use the brand detergent (KLIN) or do not used the brand detergent. But in the second survey; when being asked to see what detergent that is being used. There are greater chance that they will bring out the detergent that is commonly used  which will eventually result to the same detergent .

Answer:

C.

Step-by-step explanation:

Diameter = 11 inches.

Radius = D/2 = 5.5 inches

Volume = 4/3πr³

= 4/3(3.14)(5.5)³

= 696.6 in.³

Answer:

16

Step-by-step explanation:

The right triangle shown is a 30:60:90 triangle.

30:60:90 right triangles have a 1:sqrt(3):2 ratio between their sides.

Since the side opposite from the 30 degree is 8, and x is opposite from the 90 degree angle, 8 and x have a 1:2 ratio, or 8:16.

Answer:

A, D and B must be in a straight line.

Step-by-step explanation:

If D is between A and B, than AD+DB=AB

This would mean A, D and B would be in a straight line.

Answer:

B=25

Step-by-step explanation:

As the x values go up, the y values go down which means the line is higher on the left side than it is on the right side.

The 4th graph would be the correct one

Answer:

B. Complements of congruent angles are congruent.

Step-by-step explanation:

Angles <DCF and <FEG have angles measures that are complementary to to angles E and C.

Answer:

(a)r=15-b

11.9 Inches

(b)See attached

Step-by-step explanation:

Length of the candle =15 inch

Let b represent the burned length of the candle (in inches)

Let r represent the remaining length of the candle (in inches).

Therefore:

(a) r+b=15

r=15-b

When b=3,1 Inches

Remaining Length, r=15-3.1=11.9 Inches

(b)The graph showing te relationship between r and b is shown below.

r is plotted on the y-axis while b is plotted on the x-axis as labelled.

Formula that express r in terms of b is

[tex]r=15-b[/tex]

Remaining length of candle is 11.9 inches

Given :

A 15-inch candle is lit and steadily burns until it is burned out

Let b represent the burned length   and let r represent the remaining length  

We need to write the formula

remaining length = initial length - burned length

[tex]r=15-b[/tex]

When 3.1 inches have burned from the candle, the remaining length of the candle is inches.

b is 3.1

remaining length [tex]r=15-3.1=11.9[/tex] inches

now we graph the relationship

Graph is attached below.

Learn more :  brainly.com/question/13844802

Complete question is:

Seventy million pounds of trout are grown in the U.S. every year. Farm-raised trout contain an average of 32 grams of fat per pound, with a standard deviation of 7 grams of fat per pound. A random sample of 34 farm-raised trout is selected. The mean fat content for the sample is 29.7 grams per pound. Find the probability of observing a sample mean of 29.7 grams of fat per pound or less in a random sample of 34 farm-raised trout. Carry your intermediate computations to at least four decimal places. Round your answer to at least three decimal places.

Answer:

Probability = 0.0277

Step-by-step explanation:

We are given;

Mean: μ = 32

Standard deviation;σ = 7

Random sample number; n = 34

To solve this question, we would use the equation z = (x - μ)/(σ/√n) to find the z value that corresponds to 29.7 grams of fat.

Thus;

z = (29.7 - 32)/(7/√34)

Thus, z = -2.3/1.200490096

z = -1.9159

From the standard z table and confirming with z-calculator, the probability is 0.0277

Thus, the probability to select 34 fish whose average grams of fat per pound is less than 29.7 = 0.0277

Answer:

part a: 52%

part b: 0.4

part c: 0.24

Step-by-step explanation:

For part one, you find the frequency of the number of people that are less that 20. You add the number of tics in each bar and you divide by the total.

so for part a it is (7+6+9+4)/ (7+6+9+4+4+12+8)

for part b you add up the values that are greater than 25(less than 35)

(12+8)/total

part c you find the number of people between 25 and 30

that's 12

over total

12/total

Answer:

product = 40

Step-by-step explanation:

The conjugate of (-2 + 6i) is (-2 - 6i)

You just need to change the sign

(-2 + 6i) (-2 - 6i)

Expand:

4 + 12i + -12i - [tex]36i^{2}[/tex]

4 + 12i + -12i + 36

product = 40

Answer: The new price of  the car is $41856

Step-by-step explanation:

So we know the the original price as 43,600 which is 100% and is being dropped by 4%  so you would have to subtract 4% from a 100% and multiply it by the original price.

100% - 4% = 96%

Now 96% of the original price is the new price.

96% * 43,600= ?

0.96 * 43,600 = 41856

Answer:

-8,-6,-4,-2 is an Arithmetic sequence, because there common difference is 2.

Answer:

The area of the triangle is 18.70 sq.units.

Step-by-step explanation:

It is provided that a triangle is bounded by the y-axis, the line [tex]f(x)=y=9-\frac{2}{3}x[/tex].

The slope of the line is: [tex]m_{1}=-\frac{2}{3}[/tex]

A perpendicular line passes through the origin to the line f (x).

The slope of this perpendicular line is:[tex]m_{2}=-\frac{1}{m_{1}}=\frac{3}{2}[/tex]

The equation of perpendicular line passing through origin is:

[tex]y=\frac{3}{2}x[/tex]

Compute the intersecting point between the lines as follows:

[tex]y=9-\frac{2}{3}x\\\\\frac{3}{2}x=9-\frac{2}{3}x\\\\\frac{3}{2}x+\frac{2}{3}x=9\\\\\frac{13}{6}x=9\\\\x=\frac{54}{13}[/tex]

The value of y is:

[tex]y=\frac{3}{2}x=\frac{3}{2}\times\frac{54}{13}=\frac{81}{13}[/tex]

The intersecting point is [tex](\frac{54}{13},\ \frac{81}{13})[/tex].

The y-intercept of the line f (x) is, 9, i.e. the point is (0, 9).

So, the triangle is  bounded by the points:

(0, 0), (0, 9) and [tex](\frac{54}{13},\ \frac{81}{13})[/tex]

Consider the diagram attached.

Compute the area of the triangle as follows:

[tex]\text{Area}=\frac{1}{2}\times 9\times \frac{54}{13}=18.69231\approx 18.70[/tex]

Thus, the area of the triangle is 18.70 sq.units.