Tiffany is interested in the effects of different kinds of instructions on exam performance. she asks 60 college freshmen to each study regularly for an upcoming exam, which they will have 1 hour to take. participants are randomly assigned to one of three instruction groups: (1) complete the exam as quickly as possible, (2) complete the multiple choice before the short answers and essays, or (3) complete the short answers and essays before the multiple choice. tiffany averages the scores for each instruction group to examine whether the type of instruction made a difference in students’ test scores. which test should she use?

In the wake of the civil war, compared to the south the north had sustained very little destruction. had to create a new labor system. had more economic challenges. had to repair damaged property.

Give an example of a situation in which an individual's pursuit of economic self-interest may not benefit but instead harm the rest of society

Danilo has been working for metropolitan taxi for three months. he expected that his job would be to drive around the city, pick up fares, and drop them off at their desired locations, but in his first few days on the job he realized that the job entails much more. he must keep his taxi cab clean and neat, and some days he will be stationed at the shop and go to people's houses to pick them up and bring them to the local airport. within a few months, he has learned that taxi drivers often express frustration with the people they call "civilians"—that is, non–taxi drivers, whose driving skills they complain about incessantly. in his first few months on the job, describes what danilo is undergoing.