_ J'" . The thicknesses of glass sheets produced by a certain process are normally distributed with a mean of u = 3.00 mm and a variance of oz = 0.12 mm. a) What is the probability that a glass sheet is thicker than 3.2 mm? b) What is the probability that a glass sheet is thinner than 2.7 mm? c) What is the value of c for which there is a 99% probability that a glass sheet has a thickness within the interval [3.00 c. 3.00 + c]