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.

Answers

Answer 1

Answer:

Vitamin D and Osteoporosis

a. This is an observational study.  The researcher is trying to observe the two groups of women who suffer from osteoporosis.  She did not apply any treatment on any group, as is the case with experimental researches.

b. The treatment variable is the amount of exposure to sunshine.

Step-by-step explanation:

This study is an observational research because the researcher lacks the control over the variables, especially the amount of exposure to sunshine.  She is merely observing what has occurred previously.  On the other hand, an experimental study will involve the application of some treatments to one group of women and then the recording of the effects.  But in this case, the researcher merely recorded the effects that had occurred without applying any treatment to any group.


Related Questions

find the product of 1x6x6

Answers

36 is the answer yes yes yes

Answer:

36

Step-by-step explanation:

1x6=6

6x6=36

Hope this helps! :)

What are verbs? Example ​

Answers

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


The paved area is a square with sides 2 m long.
The paving stones for this area are squares that measure 50 cm by 50 cm
How many paving stones are needed?

Answers

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

Find the area of the triangle.
3 yd!
2.
12 yd
The area of the triangle is
square yards.

Answers

Area is 18 yards hoped this help

Write as an expression and solve (show your work!).
One-fourth the difference between twenty-one and five

Answers

Answer:

4

Step-by-step explanation:

1 / 4 x (21 - 5) =

1/4 x 16 = 4

Hope that helps!

] 8 Which expression is equivalent to 12x + 3y - 9x ?
А. 3x + Зу
В. бxy
С. 12х – бу
D. x+y

Answers

the correct is A. 3x+3y

Classify the following triangle. Check all that apply.​

Answers

Answer:

B & F

Step-by-step explanation:

Answer:

Right

Isosceles

But that’s all I got

Step-by-step explanation:

Question 3
1 pts
• A solar panel absorbs 6,771 J of radiant energy, and produces 3,291 ) of
electrical energy. What is it's percent efficiency?
(make sure you multiply x100 to get a % between 0 and 100)

Answers

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%.

HELPPPPPP ANYBODY KNOW????

Answers

All the angles should add up to 360
So you know 1 is 110
But you also know 1 is 90 because of the square so you know half is equal to 200
So you are working with 160=360-200
So now you look at the number left and say what number can be doubled and still have enough left over to add 10.
So I guess 50 times 2 is 100
And 50 plus 10 is 60
So check does this add up to be 160?yes
So x is 50
Good luck
Brainliest would be appreciated

The Harris Poll tracks the favorite sport of Americans who follow at least one sport. 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%. Consider a survey in which 344 college undergraduates who follow at least one sport were asked to identify their favorite sport produced the following results:

Professional Football Baseball Men's college football Auto racing Men's professional basketball IceHockey OtherSports
111 39 46 14 6 20 108
Do college undergraduates students differ from the general public with regard to their favorite sports? Use x= .05.

Answers

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:

Professional Football = 111 Baseball = 39 Men's college football = 46 Auto racing = 14 Men's professional basketball = 6 Ice Hockey = 20 Other Sports = 108

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

Pro football = 111/344 = 0.3226 = 32.26% (-0.74). Baseball = 39/344 = 0.1133 = 11.33% (-3.67). Men's college football = 46/344 = 0.1337 = 13.37% (+3.37). Auto racing = 14/344 = 0.0406 = 4.06% (-2.94). Men's professional basketball = 6/344 = 0.0174 = 1.74% (-3.26). Ice Hockey = 20/344 = 0.0581 = 5.81% (+0.81). Other Sports = 108/344 = 0.3139 = 31.39% (+5.39).

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.

Learn more about percentages in https://brainly.com/question/6498833

One year Hank had the lowest ERA (earned-run average, mean number of runs yielded per nine innings pitched) of any male pitcher at his school, with an ERA of 3.36 . Also, Jane had the lowest ERA of any female pitcher at the school with an ERA of 3.49 . For the males, the mean ERA was 4.449 and the standard deviation was 0.792 . For the females, the mean ERA was 5.091 and the standard deviation was 0.669 . Find their respective z-scores. Which player had the better year relative to their peers, Hank or Jane

Answers

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

someone help what the answer


Solve the following proportion: x 65 thousand
---- =. ------------
10 million. 40 million

Express your answer as a value written in standard form.

Answers

Answer:

2600000000000000000000000000000000000

Step-by-step explanation:

65 thousand times 40 million times 10 million

Answer:

great question

Step-by-step explanation:

Evaluate the expression when b=-7 and c=2.
b-6c
X 5
?

Answers

Answer:

-19

Step-by-step explanation:

-7 - 6(2) =

-7 - 12 =

-19

If the probability of having rain tomorrow is 60%, what is the probability of not having rain tomorrow?

Answers




Answer:



40%


Explanation 100-60=40


Can someone help me please?

Answers

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).

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

Answers

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:

https://brainly.com/question/20690803

#SPJ2

1. An airplane flies with a constant
speed of 740 miles per hour. How
far can it travel in 2 hours?

Answers

Answer:

740×2= 1480 in 2 hours

hope this helps :)

a store charges 32% extra for credit items. if the cash price is $1100, what is the credit price?​

Answers

Answer:

$1452

Step-by-step explanation:

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

find the value of 2xy+3yz-xyz, when x=2, y=-2, z=4​

Answers

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!

To the nearest inch, a door is 75 in. tall and 35 in. wide. What is the ratio of the
width to the height?

Answers

Answer:

35 in to 75in

Step-by-step explanation:

Please I need help ASAP

Answers

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

When you stand on snow, the average pressure P (in pounds per square inch) that you exert on the snow varies inversely with the total area A (in square inches) of the soles of your footwear. Suppose the pressure is 0.43 pound per square inch when you wear the snowshoes shown. Write an equation that gives P as a function of A. Then find the pressure if you wear the boots shown. (A=400in^2)

Find the pressure if you wear the boots shown below. (A=60in^2)

Answers

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.

What is pressure?

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.

Learn more about Pressure:

https://brainly.com/question/356585

ABCD is a parallelogram. If m/CDA = 63, then m/ABC = ? . The diagram is not to scale

Answers

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

on a nice day there are 90% of children playing outside during recess. if there are 150 children how many of them are playing outside

Answers

Answer:

150.9  ?

Step-by-step explanation:

At the city museum, child admission is $6.40 and adult admission is $9.90. On Saturday, twice as many adult tickets as child tickets were sold, for a total sales of $733.60. How many child tickets were sold that day?

Answers

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

Solve the Equation
-8.3 = d+4.7

Answers

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!!

hi everyone i know all the ansers but i wanna help people too 9x8 2x12

Answers

First answer is 72 and second is 24

Find (x + 4)(x2 + x - 2). Write your answer in standard form.
Answer please

Answers

Answer:

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

Step-by-step explanation:

Raina picks 20 flowers
1/4 are roses 2/5
are daisies
How many flowes are lilies?

Answers

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

Please help math 1-2 high school solving proofs.

Answers

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 :)

Other Questions
his minor mineral is absorbed in the stomach and is in the blood within minutes after consumption a. selenium b. chromium c. boron d. fluoride Enter your answer in the provided box. How many moles of solute particles are present in 1 L (exact) of aqueous 1.90 M KBr? mol of particles How do state governments tax consumers and vendors? Give examples of vendor and consumer taxes. (Site 2). Why did Waldie believe the pardon was a mistake? Taken together, the Necessary and Proper Clause and the Commerce Clause, provides justification for: Let UNARY-SSUM be the subset sum problem in which all numbers are represented in unary. Why does the NP completeness proof for SUBSET-SUM fail to show UNARY-SSUM is NP-complete? Show that UNARY-SSUM ? 160 students went on a field trip. Five buses were filled and 15 students traveled in cars. How many students were in each bus?Each bus had ____ students. a raster data model tends to be better representations of reality due to the accuracy and precision of points, lines, and polygons over the vector model. group of answer choices true false when considering modes of entry, christopher bartlett and sumantra ghoshal suggest that companies based in developing nations should The 5Ss developed by the Japanese do NOT include A. standardize. B. sort/segregate. C. safety. D. simplify/straighten. Which development MOST likely resulted from these court decisions?A Use of Navajo Code Talkers in the 1940sWidespread enactment of segregation lawsEnforcement of prohibition laws in the 1930sMass deportations during the Great Depression Which substituents will direct the incoming group to the meta position during electrophilic aromatic substitution? spanish settlers in the southwest received encomiendas, or ______. a person diagnosed with milk allergy would be sensitive to the milk's the separation of the rotational lines in the p and r branches of 127i 35cl is 0.2284 cm1 . calculate the bondlength. our textbook argues that, in contrast to tourism in north america and europe, tourism in the developing world is characterized by which of the following? Both prices and output will rise along an upward-sloping AS curve if the AD curve shifts _____ (leftward/rightward) the demand for gasoline is p = 5 0.002q and the supply is p = 0.2 0.004q, where p is in dollars and q is in gallons. What is the logarithmic function for log2 7 = x the leeward sides of mountains are typically dry and are often arid enough to be referred to as ________.