(R programming) P1. Heights of seedlings Exercise 8.6 reported heights (in mm) of 55.5, 60.3, 60.6, 62.1, 65.5, and 69.2 for six seedlings fourteen days after germination. (Provide the script below)

a. Verify that the 95% confidence interval for the population mean is (57.3, 67.1).

b. Name two things you could do to get a narrower interval than the one in part a.

c. Construct a 99% confidence interval. Why is it wider than the 95% interval?