Zack believes that drinking milk improves memory. He conducts an experiment in which he randomly chooses a group of participants and randomly divides them into two groups. Group A drinks milk before trying to remember a list of nonsense syllables. Group B drinks nothing before trying to remember a list of nonsense syllables. The experimental group in this experiment is ____.?

The preoperational principle called centration means that the child

a. receives help from parents on difficult tasks. b. attends to each object's single most salient feature. c. seeks perceptual balance on objects' spatial layouts. d. looks directly at objects, so that images are centered.

In general, the ideal selves of older adults are

A) close to their actual selves. B) more idealized than those of younger adults. C) nonexistent, as they no longer harbor expectations for the future. D) very far from who they are at the present.