State the null and alternative hypotheses for each of the following:
a. You are investigating a complaint that “special delivery mail takes too much time” to be delivered.
b. You want to show that people find the new design for a recliner chair more comfortable than the old design.
c. You are trying to show that cigarette smoke affects the quality of a person’s life.
d. You are testing a new formula for hair conditioner and hope to show that it is effective on “split ends.”