Siblings differing in gender exert some gender socialization effects on each other

In their research on concept recognition, Rips, Shoben, and Smith found

a. that retrieval time is not a useful means of measuring concept formation. b. that all people organize their conceptual scheme of the world hierarchically. c. the Collins and Quillian model of concept organization. d. that people's system for classifying concepts is not as simple as the Collins and Quillian model suggests. e. that the Collins and Quillan model was applicable to natural concepts but not to abstract concepts.

According to the chapter The Nose Knowsabout the scent of symmetry, whatpercentage of organisms that

have ever existed on earth were unsuccessful at reproducing and left no descendents? (a) 2% (b) 40% (c) 75% (d) 99%