A vice president at a bank states that customers obtain service within an average time of 4.9 minutes of arriving at the bank's drive-up service window. However a long-time customer of the bank wants to test the hypothesis that the average time to obtain service exceeds 4.9 minutes. The customer collects data from 16 randomly selected customers, and calculates the average time to obtain service. The sample mean time is 5.3 minutes and the sample standard deviation is 1.2 minutes. The value of the test statistic, rounded to the nearest hundredth, is
a. - 5.33
b. 5.33
c. - 1.33
d. 1.33
e. cannot be determined with the information provided