"Baby Talk Magazine" reported that the mean time a mother spends changing diapers a day is 15.1 minutes. A sample of 12 moms is chosen from your neighborhood, and it is found that the mean time they spend changing diapers was 16.3 minutes with a standard deviation of 1.6 minutes. Using a level of significance of 0.05, test the claim that the average amount of time a mom spends changing diapers is greater than 15.1 minutes.

a. Determine which test statistic you will use: the standard normal distribution, or the student's t distribution. Explain why you chose this test statistic.

b. State the null and alternative hypotheses, and state the claim.

c. Test the claim at a level of significance of 0.05 and discuss your results, should you reject or not reject the null hypothesis, should you reject or except the claim.