random sample of 81 light bulbs indicates a sample mean life of 7,164 hours. a. At the 0.05 level of significance, is there evidence that the mean life is different from 7500 hours? b. Compute the p-value and interpret its meaning. c. Construct a 95% confidence interval estimate of the population mean life of the light bulbs. d. Compare the results of (a) and (c). What conclusions do you reach? e. Compare the results of parts (a) through (d) to those when the standard deviation is 1,575 hours. a. Let be the population mean. Determine the null hypothesis, H0, and the alternative hypothesis, H1. H0:H1