The General Social Survey polled a sample of 1048 adults in the year 2010, asking them how many hours per week they spent on the Internet. The sample mean was 9.79 with a standard deviation of 13.41. A second sample of 1399 adults was taken in the year 2014. For this sample, the mean was 11.62 with a standard deviation of 15.02.

Assume these are simple random samples from populations of adults. Can you conclude that the mean number of hours per week spent on the Internet increased between 2010 and 2014?

Use the α = 0.05 level.

a. State the appropriate null and alternate hypotheses.

b. Compute the test statistic.

c. How many degrees of freedom are there, using the simple method?

d. Do you reject H0? State a conclusion.