To maintain body temperature in cold weather an organism may:

A theater reported that their highest beverage sales this year

occurred during showings of The Great African Desert. However, we cannot conclude that the film affected beverage consumption because a. the placebo effect was not considered. b. only a correlation can establish causation. c. no correlation was computed. d. there was no control group.

When comparing means in a two-group design, which statistical analysis is most appropriate?

a. independent-measures t test b. repeated-measures t test c. single-factor analysis of variance d. chi-square test for independence