For the following, identify the independent variable and the dependent variable and explain why we should use a parametric or nonparametric procedure?
(a) When ranking the intelligence of a group of people given a smart pill.
(b) When comparing the median income for a group of college professors to that of the national population of all incomes.
(c) When comparing the mean reading speed for a sample of hearing-impaired children to the average reading speed in the population of hearing children.
(d) When measuring interval scores from a personality test given to a group of emotionally troubled people and comparing them to the population p for emotionally healthy people.