part b please, will thumbs up if correct

In an initial survey designed to estimate the percentage of time air-express cargo loaders are idle, an analyst found that loaders were idle in 5 of the 45 observations. a. What is the estimated percentage of idle time? (Round your answer to 2 decimal places.) Answer is complete and correct. b. Based on the initial results, approximately how many observations would you require to estimate the actual percentage of idle time to within 4 percent with a confidence of 95 percent? (Round your z value to 2 decimal places. Do not round any other intermediate calculations. Round UP your final answer to the next whole number.)