12. After examination of some thousands of observations a Six Sigma Black Belt quality engineer determined that the observed thrusts for a certain aircraft engine were approximately normally distributed with mean 1000 pounds and standard deviation 10 pounds. What percentage of such measured thrusts would you expect to be

(a) Less than 985 pounds?

(b) Greater than 1020 pounds?

(c) Between 985 and 1020 pounds?