For multiple years, an aquarium conducted a survey of a random sample of visitors as they exited the museum. The survey includes visitor demographic information, use of social media, and opinions on their aquarium visit. Most recently, the survey included195visitors over 65, of which43used a mobile device such as an Android phone or iPad during their visit.

(a) What is the margin of error of the large-sample 95% confidence interval for the proportion of visitors over 65 who used a mobile device during their visit? (Round your answer to three decimal places.)

(b) How large a sample is needed to get the common3 percentage point margin of error? Use the sample from part (a) as a pilot study to getp*. (Round your answer up to the next whole number.)

visitors