THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
Suppose that the waiting times for patients at a local hospital are normally distributed with known population standard deviation of 30 minutes.A random sample of 75 patients in the local hospital had a mean time of 90 minutes.Assume a 95% confidence interval for the population mean μ.
-Calculate the margin of error of the 95% confidence interval.

A) 5.69
B) 8.93
C) 6.79
D) 8.06