8.81 Facebook users. A Pew survey of 1802 Internet users found that 67% use Facebook.28

  1. (a) How many of those surveyed used Facebook?

  2. (b) Give a 95% confidence interval for the proportion of Internet users who use Facebook.

  3. (c) Convert the confidence interval that you found in part (b) to a confidence interval for the percent of Internet users who use Facebook.