6.57 Translating research questions into hypotheses. Translate each of the following research questions into appropriate H₀ and H_a.

1. (a) U.S. Census Bureau data show that the mean household income in the area served by a shopping mall is $42,800 per year. A market research firm questions shoppers at the mall to find out whether the mean household income of mall shoppers is higher than that of the general population.

2. (b) Last year, your online registration technicians took an average of 0.4 hour to respond to trouble calls from students trying to register. Do this year’s data show a different average response time?