Marketers want to know about the differences between men’s and women’s use of the Internet. A Pew Research poll in April 2009 from a random sample of US adults found that 2393 of 3037 men use the Internet, at least occasionally, while 2378 of 3166 women did.

a) Find the proportions of men and women who said they use the Internet at least occasionally.

b) What is the difference in proportions?

c) What is the standard error of the difference?

d) Find a 95% confidence interval for the difference between percentages of usage by men and women nationwide.