Please answer all parts as best as you can :)

. (15 points) A forester studying the effects of fertilization on certain pine forests in the Southeast is interested in estimating the average basal area of pine trees. In studying basal areas of similar trees for many years, he has discovered that these measurements (in square inches) have population standard deviation 4 square inches. If the forester samples 64 trees, nd the probability that the sample mean will be within 1 square inch of the population mean