A serious problem that can lead to suicide or a major impairment of emotional functioning, and which requires professional help, is

According to Piaget's theory, children first show or develop object permanence during the

a. sensorimotor stage b. concrete operational stage c. preoperational stage d. formal operational stage

When Chi asked child chess experts and adult chess novices to remember sequences of numbers and positions of chess pieces on a chess board, she found that

a. child chess experts remembered more number sequences and more chess piece patterns than adult chess novices did. b. adult chess novices remembered more number sequences and more chess piece patterns than child chess experts did. c. adult chess novices remembered more number sequences, but child chess experts remembered more chess piece patterns. d. child chess experts remembered more number sequences, but adult chess novices remembered more chess piece patterns.