A certain potato chip manufacturer makes extremely large bags of potato chips with a mean mass of 315g and a standard deviation of 2. Calculate each...

A certain potato chip manufacturer makes extremely large bags of potato chips with a mean mass of 315g and a standard deviation of 2.56g. Calculate each of the following probabilities.

a) What is the probability that a randomly chosen bag has a mass of less than 321g?

b) What is the probability that a bag has a mass of between 314g and 322g?