The percentage of Texans not covered by health care insurance in 2015 was 17% (The Henry J. Kaiser Family Foundation website, December 5, 2015). The Texas Health and Human Services Commission (HHSC) has been charged with conducting a sample survey to obtain more current information.

a. What sample size would you recommend if the HHSC's goal is to estimate the current proportion of Texans without health care insurance with a margin of error of .03? Use a 95% confidence level.

b. Repeat part (a) using a 99% confidence level.