The Average Life of a Certain Type and Brand of Battery

The average life of a certain type and brand of battery is 75 weeks. The average life of each of 9 randomly selected batteries is listed below.
74.5, 75.0, 72.3, 76.0, 75.2, 75.1, 75.3, 74.9, 74.8
a. Assume the battery life distribution is normal. It is of interest to know if the sample data suggest the average life is smaller than 75 weeks.
b. Compute the test statistic for the hypotheses in part (a).
Test statistic = ______________
c. Compute the approximate p-value associated with the test statistic in (b).
P-value = ______________
Conclusion: ______________
The sample data ______________ support the alternative hypothesis at the
= 0.05 level.