Your roommate asks, "Why are you studying so much?" You reply, "Because we could have a pop quiz any time during class, so I have to study constantly!" Your study habits are the result of your quiz schedule.

- Variable interval.

Explanation:

'Variable interval' schedule is demonstrated as the schedule in which a particular response or action is after an uncertain period of time which could be few hours, day, a week, etc. in order to reinforce a particular behavior or response.

In the given example, I('you' in the example) is studying as the pop quiz can be taken any time throughout the class which exemplify the 'variable interval'. The 'variable interval' has been employed for free-operant conditioning to reinforce a specific behavioral response(studying) through inconsistent rewarding schedule. Therefore, 'variable interval' is the answer.

answer = d. hope this . : -d

1. list two reasons why fossil fuels should continue to be used as a source of energy in america.