101 Laptop use in middle school. Refer to the American Secondary Education (Fall 2009) study of 106 middle school students’ usage of laptop computers, Exercise 16 .

The number of minutes per day each student used a laptop for taking notes was recorded, with the following results:

x = 13.2, s = 19.5 .

a. Find and interpret a 95% confidence interval for the variance in the amount of time per day laptops are used for taking notes for all middle school students across the country.

b. Recall that in Exercise 2.100b you concluded that the distribution of laptop usage for taking notes cannot be normally distributed. Does this compromise the validity of the interval estimate, part a ? Explain.