a. How large a sample is needed to determine the percentage of adult Americans who want help figuring out the best methods for improving their health?A previous survey indicated that 66% would like help with this important health issue.Use a 90% level of confidence and assume that you would like the sample to be within 3% of the true population proportion.

b)If the previous problem (3a) did not have a value for the sample proportion, what would happen to the sample size?There is no need to calculate the new sample size - simply comment on the effect of not knowing the sample proportion.