1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
USPshnik [31]
3 years ago
11

The data were gathered by the following procedure, reported in the study. "Between January and June 1998, parents of children ag

ed 2-16 years [...] that were seen as outpatients in a university pediatric ophthalmology clinic completed a questionnaire on the child’s light exposure both at present and before the age of 2 years." Was this study observational, or was it a controlled experiment? Explain.
Mathematics
1 answer:
WARRIOR [948]3 years ago
7 0

Answer:

This was an observational study.

Step-by-step explanation:

Given is that parents of children completed a questionnaire on the child’s light exposure both at present and before the age of 2 years.

This was an observational study since there is no treatment or control group.

We know that treatment, control groups or treatment groups are not specific to randomized control experiments.

You might be interested in
A rectangular driveway has an area of 880 square feet and a perimeter of 128 feet. What are the dimensions of the driveway?
mamaluj [8]

Answer:

Dimensions are 20 X 44 feet

Step-by-step explanation:

First we need to build two equations:

For area X times Y = 880

For Perimeter 2x + 2y = 128

Now we need to solve one so we can substitute it into the other:

2x + 2y = 128 becomes

2x = 128 - 2y and then

x = 64 - y We will substitute this into the are equation

(64 - y)y = 880

64y - y^{2} = 880

-y^{2} + 64y -880 = 0

factor out the negative

-(y^{2} - 64y +880 = 0

Factor:

-(y - 20)(y - 44) = 0

y-20 = 0 and y - 44 = 0

y = 20 and y = 44

Plugging these in two both of our formulas works

20 X 44 = 880 for area

2(20) + 2 (44) = 128 for perimeter

8 0
3 years ago
Which inequality is represented by this graph?<br><br>​
STatiana [176]

Answer:

Two-variable inequalities from their graphs (video)

Step-by-step explanation:

6 0
3 years ago
You deposit $2,000 into a saving account that gains 7% interest each year. How long will it take for your balance to
Vinil7 [7]

Answer:

its simple just divide and multipy it by 100%

Step-by-step explanation:

here

5 0
3 years ago
If no grouping symbols or exponents are in an expression, then do
kotykmax [81]

Answer:

multiplication and division

Step-by-step explanation:

6 0
3 years ago
Read 2 more answers
The triangles are similar. Find the value of x.
LUCKY_DIMON [66]

Answer: 95

Step-by-step explanation:

I am in geometry this year. We know by the AA thorem that all three angles are similar. Since both triangles have sides 45 and 40. We know that the last side has to 95.

Hope this helps :)

5 0
3 years ago
Read 2 more answers
Other questions:
  • 3/4 of 36 what Is the answer too that
    12·1 answer
  • What is another way to name 1/4
    9·1 answer
  • 5% of Mr. Larios‘s jokes are funny if he makes 16 funny jokes this year how many total jokes does he make
    10·2 answers
  • Can you guys help me?
    10·1 answer
  • Ariel's bill for brunch at a restaurant was $76. She left a 15% tip. What was the amount of the tip?
    10·2 answers
  • Hi lol i don't need help with anything
    5·1 answer
  • At the store 6 pounds of bananas cost $1.95. Enter the amount of 18 bananas would cost.
    14·1 answer
  • Can a linear graph bend?
    6·1 answer
  • I am a two digit number. My tens place is 8 more than my ones place.
    6·2 answers
  • Clues:
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!