Diane understands that her collection of penguin toys can be added to her collection of owl toys to make a collection of bird toys. This illustrates the concrete operation called:

Among which of the following ethnic groups are gays and lesbians least likely to be "out?"

a) African American b) Native American c) Caucasian American d) Asian American

Mike has very high levels of well-being, particularly concerning his job. His boss is concerned because these high levels of happiness can be related to

A) complacency. B) drug use. C) perfectionism. D) severe depression when someone points out the realities of his situation. E) increases in motivation that lead people to set impossible unattainable goals.