Researcher Sandra Bem describes persons who had high scores in both masculine and feminine traits as

It is hard to teach pigs to use piggy banks because

(a) pigs cannot be classically conditioned; they extinguish right away (b) pigs cannot be operantly conditioned; they extinguish right away (c) pigs are simply not intelligent enough to learn (d) behavior is not infinitely flexible (e) any behavior can be conditioned, as shown by Skinner

The general factor of intelligence is:

a. The idea that each ability can be considered a separate intelligence b. When one of the intellects becomes more dominant than the others c. A core capability for all cognitive abilities d. The fact that IQ scores cannot be changed with experience