The loaves of rye bread distributed to local stores by a certain bakery have an average length of 30 centimeters and a standard deviation of 2 centimeters. Assuming that the lengths are normally distributed, what percentage of the loaves are
a) Longer than 31.7 centimeters?
b) Between 29.3 and 33.5 centimeters in length?
c) Shorter than 25.5 centimeters?