2. (10pts) The manager of a convenient store wants to estimate the proportion of time staffs spend checking merchandise on the shelf. The manager wants a 99% confidence that the resulting estimate will be within 10% of the true value. a) If the manager feels the proportion is 50% before making observations on the proportion, what sample size should she use? b) Suppose that, in the first A observations stock clerks were found to be checking merchandise B times. (i) Determine the values of integers A (100 A 150), and B (10 B