Vitamin D is important for the metabolism of calcium and exposure to sunshine is an important source of vitamin D. A researcher wanted to determine whether osteoperosis was associated with a lack of exposure to sunshine. He selected a sample of 250 women with osteoperosis and an equal number of women without osteoperosis. The two groups were matched - in other words they were similar in terms of age, diet, occupation, and exercise levels. Histories on exposure to sunshine over the previous twenty years were obtained for all women. The total number of hours that each woman had been exposed to sunshine in the previous twenty years was estimated. The amount of exposure to sunshine was compared for the two groups.

Required:
a. Determine whether this is a controlled experiment or an observational study.
b. Identify the treatment variable.

Answer:

2600000000000000000000000000000000000

Step-by-step explanation:

65 thousand times 40 million times 10 million

Answer:

great question

Step-by-step explanation:

Answer:

The calculated  χ²  = 20.779  falls in the critical region  χ² ≥ 14.46 so we accept the null hypothesis that all the means are equal and college undergraduates students do not differ from the general public with regard to their favorite sports.

Step-by-step explanation:

1) We set up our null and alternative hypothesis as

H0: the college undergraduates students do not differ from the general public with regard to their favorite sport

H0:  μ1= μ2=μ3=μ4= μ5=μ6=μ7=μ

against the claim

Ha: the college undergraduates students differ from the general public with regard to their favorite sport

2) The significance level alpha is set at 0.05

3) The test statistic under H0 is ( Pearson goodness of fit test )

χ²= ∑ (O - E)²/ E   where O is the observed and E is the expected frequency

which has an approximate chi square distribution with 6 (n-1) d.f

4) Computations:

Under H0 , the observed frequencies are :

 Observed       Expected          (O-E)          (O-E)²                   (O-E)²/E

 111                    (0.33*344)=

                             113.52           -2.52             6.3054              0.0555

  39                      51.6               -12.6              158.76               3.0767

  46                       34.4               11.6               134.56              3.911

  14                       20.64              -6.64           44.0896           2.136

  6                        17.2                   -11.2            125.44             7.293

 20                       17.2                    2.8             7.84                 0.4558

108                       89.44                18.56           344. 4736       3.8514              

                              344                                                             20.779    

5) The critical region is χ² ≥  χ² (0.025)6 = 14.45

6) Conclusion:

The calculated  χ²  = 20.779  falls in the critical region  χ² ≥ 14.46 so we reject the null hypothesis that all the means are equal and college undergraduates students do not differ from the general public with regard to their favorite sports.

Given that all the results are lower or higher in percentage, but they do not exceed the 5.5% threshold, it can be said that college undergraduates students do not differ from the general public with regard to their favorite sports.

Since the Harris Poll tracks the favorite sport of Americans who follow at least one sport, and results of the poll show that professional football is the favorite sport of 33% of Americans who folllow at least one sport, followed by baseball at 15%, mens college football at 10%, auto racing at 6%, mens professional basketball at 5%, and ice hockey at 5%, with other sports at 26%, considering a survey in which 344 college undergraduates who follow at least one sport were asked to identify their favorite sport produced the following results:

To determine if college undergraduates students differ from the general public with regard to their favorite sports, the following calculation must be performed:

Therefore, given that all the results are lower or higher in percentage, but they do not exceed the 5.5% threshold, it can be said that college undergraduates students do not differ from the general public with regard to their favorite sports.

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Answer:

1= A

2= C

Step-by-step explanation:

I think this is right I'm not sure but I think it is.

hope this helps :)

Answer:

x child tickets, y adult tickets

6.40x+9.50y=1260.70

x+y=150

64x+95y=12607

x+y=150

If you solve this, you have to get x=53, y= 97.

So 53 child tickets and 97 adult tickets

Given:

A line segment AB.

A point is [tex]\dfrac{3}{10}[/tex] of the way from A to B.

To find:

The coordinates of that point.

Solution:

Section formula: If a point divide a line segment in m:n, then

[tex]Point=\left(\dfrac{mx_2+nx_1}{m+n},\dfrac{my_2+ny_1}{m+n}\right)[/tex]

From the given figure, it is clear that the two end points of the line segment are A(-4,-5) and B(12,4).

Let the unknown point be P. The point is [tex]\dfrac{3}{10}[/tex] of the way from A to B. It means,

[tex]\dfrac{AP}{AB}=\dfrac{3}{10}[/tex]

Let AP and AB are 3x and 10x, then

[tex]\dfrac{AP}{PB}=\dfrac{AP}{AB-AP}[/tex]

[tex]\dfrac{AP}{PB}=\dfrac{3x}{10x-3x}[/tex]

[tex]\dfrac{AP}{PB}=\dfrac{3x}{7x}[/tex]

[tex]\dfrac{AP}{PB}=\dfrac{3}{7}[/tex]

It means, point P divided the line segment in 3:7.

Using section formula, we get

[tex]P=\left(\dfrac{3(12)+7(-4)}{3+7},\dfrac{3(4)+7(-5)}{3+7}\right)[/tex]

[tex]P=\left(\dfrac{36-28}{10},\dfrac{12-35}{10}\right)[/tex]

[tex]P=\left(\dfrac{8}{10},\dfrac{-23}{10}\right)[/tex]

[tex]P=\left(0.8,-2.3\right)[/tex]

Therefore, the coordinates of the required point are (0.8, -2.3).

Answer:

-16

Step-by-step explanation:

2xy + 3yz - xyz

x = 2, y = -2, z = 4

First, plug these values into the equation.

2(2)(-2) + 3(-2)(4) - (2)(-2)(4) = ?

Next, multiply the parentheses.

(-8) + (-24) - (-16) = ?

When you add a negative, you are actually subtracting the number. And when you subtract a negative, you are actually adding the number. Apply this to the equation.

-8 - 24 + 16 = ?

Now, simplify from left to right.

-32 + 16

-16

Your answer is -16.

Hope this helps!

9514 1404 393

Answer:

  48.6%

Step-by-step explanation:

Efficiency of energy conversion is the quotient of output energy and input energy.

  (3291 J)/(6771 J) × 100% ≈ 48.6%

The solar panel's conversion efficiency is about 48.6%.

_____

Additional comment

With current (2021) technology, the best efficiency one can expect from a solar panel is in the neighborhood of 23%.

Answer:

36

Step-by-step explanation:

1x6=6

6x6=36

Hope this helps! :)

Answer:

$1452

Step-by-step explanation:

[tex]CP=1100*1.32=$1452[/tex]

Answer:

35 in to 75in

Step-by-step explanation:

Answer:

Step-by-step explanation:

2 meters = 200 cm

200 cm × (1 block)/(50 cm) = 4 blocks

4 blocks by 4 blocks = 16 blocks

Answer:

16 paving stones

Step-by-step explanation:

1 m = 100 cm

The square has sides 200 cm long

Its area is 200(200) = 40000 sq cm

Each paving stone has an area of 50(50) = 2500 sq cm

So 40000/2500 = 16 paving stones

Answer:

-19

Step-by-step explanation:

-7 - 6(2) =

-7 - 12 =

-19

Answer:

4

Step-by-step explanation:

1 / 4 x (21 - 5) =

1/4 x 16 = 4

Hope that helps!

Answer:

0.43*0.43

Step-by-step explanation:

The pressure on the snow if the area of the footwear is 400 in² is 0.0645 pounds per square inch.

The force applied perpendicular to an object's surface per unit area across which that force is spread is known as pressure.

[tex]P= \dfrac{W}{A}[/tex]

As it is given that the pressure is inversely proportional to the area of the footwear. Therefore, the relation can be written as,

[tex]P\propto \dfrac{1}{A}\\[/tex]

Now, introducing a constant to remove the proportionality symbol, w that is the weight of the person, therefore,

[tex]P= \dfrac{W}{A}[/tex]

Now, as the area of the shoe is 60in²,  the pressure on the snow is  0.43 pounds per square inch. Therefore, the value of w can be written as,

[tex]0.43= \dfrac{W}{60}\\\\W = 25.8\rm\ pounds[/tex]

Now, the pressure on the snow if the area of the footwear is 400 in².

[tex]P= \dfrac{W}{A}\\\\P= \dfrac{25.8}{400}\\\\P = 0.0645 \rm\ pounds\ per\ inch^2[/tex]

Hence, the pressure on the snow if the area of the footwear is 400 in² is 0.0645 pounds per square inch.

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Answer:

It's 28!

Step-by-step explanation:

Answer:

28 in

Step-by-step explanation:

convert the whole thing to inches

5ft 8in = 68 in

8ft = 96 in

96-68 = 28 in

Answer:

7 of the flowers were lilies.

Step-by-step explanation:

8 daises and 5 roses were picked. 8 + 5 = 13    20 - 13 = 7

7 of the flowers were lilies

Answer:

Hi! Hope this helps!

Step-by-step explanation:

A verb is used to describe actions.

Example: I JUMPED over the rock. In this sentence the verb is JUMPED

a ver

Step-by-step explanation:

a verb is a word used to describe an action , state , occurrence and forming the main part of a predicate of a sentence

when calculating present value, the _____ interest rate, the smaller the present value amount.

* smaller

* larger,✓

The correct value is,

''When calculating present value, the smaller the interest rate, the smaller the present value amount.''

What is Simple interest?

A quick and easy method of calculating the interest charge on a loan is called a Simple interest.

Given that;

To calculating the present value, The smaller the present value.

Now,

The correct value is,

''When calculating present value, the smaller the interest rate, the smaller the present value amount.''

Learn more about the simple interest visit:

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#SPJ2

Answer:

150.9  ?

Step-by-step explanation:

Answer:

X^3 + 5x^2 + 2x - 8

Step-by-step explanation:

Answer:

d = -13

Step-by-step explanation:

-8.3 = d + 4.7

-8.3 - 4.7 = d

-13 = d

-8.3=d+4.7

What you want to do is flip the equation like this:

d+4.7=-8.3

The next step is to subtract 4.7 from both sides of the equation:

d+4.7=-8.3

-4.7 (both sides)

this equals to d=-13

Your final answer is d=-13 (negative 13).

Hope this helps!!

Answer:

B & F

Step-by-step explanation:

Answer:

Right

Isosceles

But that’s all I got

Step-by-step explanation:

it’s 63 because the sides are equal on both sides

Answer:

740×2= 1480 in 2 hours

hope this helps :)

Answer:

Hank had a z-score of -1.375.

Jane had a z-score of -2.39.

Jane had the better year relative to their peers, due to her lower z-score.

Step-by-step explanation:

Z-score:

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Hank:

ERA of 3.36. For the males, the mean ERA was 4.449 and the standard deviation was 0.792. This means that we have to find Z when [tex]X = 3.36, \mu = 4.449, \sigma = 0.792[/tex]. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{3.36 - 4.449}{0.792}[/tex]

[tex]Z = -1.375[/tex]

Hank had a z-score of -1.375.

Jane

ERA of 3.49.  For the females, the mean ERA was 5.091 and the standard deviation was 0.669. This means that we have to find Z when [tex]X = 3.49, \mu = 5.091, \sigma = 0.669[/tex]. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{3.49 - 5.091}{0.669}[/tex]

[tex]Z = -2.39[/tex]

Jane had a z-score of -2.39.

Which player had the better year relative to their peers, Hank or Jane

Low ERA is good, high is bad. This means that whoever had the lower z-score had the better year, and in this case, it's Jane