A population has a mean of 400 and a standard deviation of 60. Suppose a sample of size 100 is selected and x is used to estimate μ. a. What is the probability that the sample mean will be within +/- 6 of the population mean (to 4 decimals)? b. What is the probability that the sample mean will be within +/- 16 of the population mean (to 4 decimals)?