9. The human brain's delay in response to a sound has been found to be 5.68 milliseconds. A random sample of 10 participants is selected, and each subject
is asked to go without sleep for 24 hours before a test for brain stem auditory
response latency. The average latency is found to be 5.85 milliseconds, with s
= 0.14. Test the hypothesis that lack of sleep has no effect on average latency.

Asales representative from a local radio station is trying to convince the owner of a small fitness club to advertise on her station. the representative says that if the owner begins advertising on the station today, the club's total number of members will grow exponentially each month. she uses the given expression to model the number of club members, in hundreds, after advertising for t months.