Answer: B. Controlled experiment
Step-by-step explanation:
This is a controlled experiment because the variables in the question are manipulated by the researcher. We are told that while one group watches television before going to sleep, the other group does not.
The controllers won't have control over the variables that were used if it was an observational study while for a survey, it has to do with collection of information regarding certain topics or happenings in order to have people's perception on the topic or area of interest.
Answer
Find out the how many kilobytes have been downloaded so far .
To prove
As given
While waiting for a video game to download.
notice that 30 percent of 32000 kilobytes have been downloaded so far .
30% is written in the decimal form.

= 0.30
kilobytes uses in downloaded = 0.30 × 32000
= 9600 kilobytes
Therefore 9600 kilobytes have been downloaded so far .
Answer:
x = 3/7
Step-by-step explanation:
Decimal Form : x = 0.428571 repeated
567 = 500+60+7
4*567 = 4*(500+60*7)
4*567 = 4*500 + 4*60 + 4*7 ... see note below
4*567 = 2000 + 240 + 28
4*567 = 2268
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note: multiply the outer term 4 by each term inside the parenthesis to use the distributive property. The general distributive property is a*(b+c) = a*b+a*c. This can be extended to a*(b+c+d) = a*b+a*c+a*d. You can have as many terms as you like inside the parenthesis.