The oil-producing countries decide together how much old they will produce in an attempt to maximize profits. what is this an example of?

Apsychologist has developed a series of personality inventories and wants to determine if they are valid. one of the scales measures perfectionism, so he asks a colleague for advice on how to establish the validity of this scale. the colleague tells him that if he were to find a sample of people with personality disorder, these people would obtain high scores on a scale that measures perfectionism.

It is widely assumed that people need to engage in intellectual activities such as solving crossword puzzles or mathematics problems in order to maintain mental sharpness as they age. in fact, however, simply talking to other people—that is, participating in social interaction, which engages many mental and perceptual skills—suffices. evidence to this effect comes from a study showing that the more social contact people report, the better their mental skills. which of the following, if true, most seriously weakens the force of the evidence cited? (a) as people grow older, they are often advised to keep exercising their physical and mental capacities in order to maintain or improve them. (b) many medical conditions and treatments that adversely affect a person's mental sharpness also tend to increase that person's social isolation. (c) many people are proficient both in social interactions and in solving mathematical problems. (d) the study did not itself collect data but analyzed data bearing on the issue from prior studies. (e) the tasks evaluating mental sharpness for which data were compiled by the study were more akin to mathematics problems than to conversation.

Of the 8 territories that were brought under the flag of the united states by 1853, which one do you think was the most important addition to the growth of the united states?