About what percentage of all persons receiving a primary diagnosis have symptoms that meet the criteria for a second diagnosis?

Time spent in good child care has no significant effect on the security of a child's attachment

Indicate whether this statement is true or false.

Why is it generally easier to extinguish behaviors that have been reinforced on fixed rather than variable schedules of reinforcement?

a) Extinction is built into fixed schedules. b) Reinforcement on fixed schedules is predictable, so it is easier to determine when it has stopped. c) Fixed schedules tend to lead to high rates of behavior, which over time are tiring to participants. d) Low rates of behavior occurring in fixed schedules mean that the rate of behavior is so close to extinction that all it needs is a little push.