Michael is a college student. he can either buy a textbook for $100 or save up for a road trip he wants to take during the summer. this illustrates the principle that a. rational people think at the margin. b. people respond to incentives. c. trade can make everyone better off. d. people face trade-offs.

Explanation:

Michael is demonstrating a rational behaviour, because he's trying to make a choice between a necessity and vanity.

So, this thinking process talks about he's ability to rationalise between options.

1. government controls industry through policy

2.government is both a consumer and a producer

4. government can use policy t influence economy

i did this!

answer:

d. because dr. laguardia selected a widely used measure, his study generalizes to has strong external validity. external validity has limited external validity. other applications of this measure.

the widely used measure that he applied to his experiment was the benton facial recognition test. it employed on to football players and as result, only players who suffered brain concussions did not pas this test. and although it has an external validity, it is limited because it isn't general to apply to other population.