a)A sample of 30 patients in a doctor's office showed that theyhad to wait an average of 35 minutes before they could see thedoctor. The sample standard deviation is 9 minutes. Assume thepopulation of waiting times is normally distributed.At 90%confidence, compute the margin of error.
b)Consider the population of electric usage per month forhouses. The standard deviation of this population is 119kilowatt-hours. What is the smallest sample size to provide a 90%confidence interval for the population mean with a margin of errorof 32 or less? (Enter an integer number.)
