Skull size of a population of rats follows a normal populati

Skull size of a population of rats follows a normal population with std dev = 10mm. Y bar = mean skull size of a random sample of 64 individuals from the population. µ = population mean skull size. Find the two probabilities

P(µ - 2.5mm < Ybar < µ + 2.5mm)

P(µ - 3.75mm < Ybar < µ + 1.25mm)