In which stage of prenatal development does the child undergo astoundingly rapid change, including dramatic changes in proportion and weight?

When a t test is applied to experimental research data, the groups are

being compared with regard to their performances on the a. independent variable b. dependent variable c. confounding variable d. controlled variable

The first experiments in cognitive psychology were based on the idea that mental responses can be

a. measured directly. b. inferred from the participant's behavior. c. measured by comparing the presentation of the stimulus and the participant's response. d. measured by comparing responses among different participants.