You Have Been Asked to Observe the Shift Supervisor at the Process

You have been asked to observe the shift supervisor at the process test plant for Hudson Chemical Co.to estimate the proportion of time she spends answering questions for the operators.Your 30 observations have revealed the following:
(a)Based on the preliminary data,calculate the proportion of time she spends answering questions for the operators.
(b)Calculate the sample size needed to estimate the proportion of time she spends answering questions for the operators.Assume a 90% confidence that the results will lie within 5% of the true value.