Question: A poll of 1,286 young adult cell phone users was conducted in March 2006. These cell phone users, aged 18 29, were actively engaged in multiple uses of their cell phones. The data suggest that 707 took still pictures with their phones, 604 played games, and 360 used the Internet (Extracted from Poll: Cellphones Are Annoying but Invaluable, usatoday.com, April 3, 2006). Construct a 95% confidence interval estimate of the population proportion of young adults that used their cell phone to

a. take still pictures.

b. play games.

c. use the Internet.

d. You have been asked to update the results of this study. Determine the sample size necessary to estimate the population proportions in (a) through (c) to within 0.02 with 95% confidence.