<span>Dr.Murphy is most likely a developmental psychologist.
Developmental psychologists study how and why individuals change and progress throughout their lifespan in terms of their social, moral, emotional and cognitive functions. If Dr.Murphy is studying cohort of school children and following their progress through to their college years, he is tracking their development and progress through their growing years in terms of their moral, social, cognitive and biological growth.</span><span>
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I believe the answer is intermittent reinforcement.
intermittent reinforcenet refers to the process of imposing operant conditioning in which the reinforcement is being done in a random time.
The purpose of doing intermittent reinforcement is to make them able to push the subject into doing things to even if they receive no reward for it.<span />
<span>The answer is swimming. It
is an activity which is known to a human since prehistoric times. The history
of swimming goes way back centuries ago. One of the museums in Turin, there is
a bas-relief portraying a man doing swimming. Movement of the swimmer was
captured in the ancient Egyptian sculptor’s chisel, as two drops of water
similar to the essentials of modern breaststroke. It is said to be estimated
about 3000 years of age.</span>
Changes in cost of inputs, natural disasters, new technology, taxes, subsidies, and government regulation all affect the cost of production.