Statistics and probablity assignment due 11:59 est today open office only please

1. A normal random variable has unknown mean and known standard deviation in E1. We wish to sample this enough times to be (E2)% confident that the mean of our sample is within E3 of the true mean. How large of a sample size is needed? Give the minimal such sample size in B1. Accuracy in B1 is allowed to within 5% - remember that sampling is expensive!