The percentage of people not covered by health care insurance in 2003 was 15.6% (Statistical Abstract of the United States, 2006). A congressional committee has been charged with conducting a sample survey to obtain more current information.

a. What sample size would you recommend if the committee's goal is to estimate the current proportion of individuals without health care insurance with a margin of error of .03 (to the nearest whole number)? Use a 95% confidence level.

b. Repeat part (a) using a 99% confidence level (to the nearest whole number).