The manager of a newly opened gift boutique wants to estimate the average expenditure of his customers using a confidence interval. He estimates that the population standard deviation is approximately $28.00. Please, use the following table (do not use Excel) to answer the questions about ze . Do not round the values me and keep the number of decimal places as in the table. Table of zo and za for most common a values NE 0.005 0.01 0.02 0.03 0.04 0.05 0.06 0.1 2.575 2.33 2.05 1.88 1.75 1.645 1.555 1.28 2.81 2.575 2.33 2.17 2.05 1.96 1.88 1.645 (a) For a 99% confidence level, find the appropriate sample size necessary to achieve a margin of error of 9.00. Determine E= = Round your answer (n] UP to the next whole number. The required sample size r is (b) For a 90% confidence level, find the appropriate sample size necessary to achieve a margin of error of 9,00. Determine Ju = Round you's answer (n] UP to the next whole number. The required sample size no is