Researchers randomly choose two groups from 15 volunteers. Over a period of 9 weeks, one group watches television before going to sleep, and the other does not. Volunteers wear monitoring devices while sleeping, and researchers record dream activity. Which type of study method is described in each situation? Group of answer choices a) observational study b) controlled experiment c) survey

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.

x is greater than 5

step-by-step explanation:

2x+7 is greater than 17

    -7                           -7

2x is greater than 10

divide by 2 each side

x is greater than 5

step-by-step explanation:

ok one would be money, and the other would be refreshments or something similar. if each bag of popcorn is 5.00 and each drink is half of that that means drinks are 2.50 the proper way to do that would to look and see how much of each you can buy without exceeding a limit of 30.00