The Know Nothing Party ran candidates on a platform that immigrants were a threat to ________

The randomized pretest-posttest, control-group design is an improvement over the randomized posttest-only, control-group design because

A) the former adds an additional control group. B) the latter employs randomization only at the time of the posttest. C) the former adds a pretreatment measurement of the independent variable. D) the former adds a pretreatment measurement of the dependent variable.

The spread around the center of a distribution can be measured three ways. The __________

gives the highest and lowest ends of a set of numbers. Fill in the blanks with correct word