For each of the following, write out the null and alternative hypotheses, being sure to state whether the alternative is one-sided or two-sided.
a) A company reports that last year, 40% of their reports in accounting were on time. From a random sample this year, they want to know if that proportion has changed.
b) A company wants to know if average click-through rates (in minutes) are shorter than the 5.4 minutes that customers spent on their old website before making a purchase.
c) Last year, 42% of the employees enrolled in at least one wellness class at the company's site. Using a survey, they want to know if a greater percentage is planning to take a wellness class this year.
d) A political candidate wants to know from recent polls if she's going to garner a majority of votes in next week's election.