Need i don't get what the question is asking

What is the fewest number of full weeks briyana would have to work to have enough money? 8 weeks9 weeks 10 weeks11 weeks

Just tell me how to set up the equation.

Thompson and thompson is a steel bolts manufacturing company. their current steel bolts have a mean diameter of 127 millimeters, and a variance of 36. if a random sample of 35 steel bolts is selected, what is the probability that the sample mean would differ from the population mean by greater than 0.5 millimeters? round your answer to four decimal places.