Regeneration is almost nonexistent in the __________ of adult mammals; in their __________, it is at best a hit-or-miss affair

The use of tind rests on the assumption that _____

a. each subject is randomly selected b. each subject is randomly assigned to a group c. the population sizes are equal d. the population means are equal

In comparison to NREM dreams, REM dreams ____

a. are less likely to include striking visual imagery b. are more likely to include complicated plots c. do not contain violence d. are almost always less than five minutes