A cable television customer call center has a goal that states that the median time for each…

A cable television customer call center has a goal that
states that the median time for each completed call should not exceed four
minutes. If calls take too long, productivity is reduced and other customers
have to wait too long on hold. The operations manager does not want to
incorrectly conclude that the goal isn’t being satisfied unless sample data
justify that conclusion. A sample of 12 calls was selected, and the following
times (in seconds) were recorded:

a. Construct the appropriate null and alternative
hypotheses.

b. Based on the sample data, what should the operations
manager conclude? Test at the 0.05 significance level.