The computer chips in today's notebook and laptop computers are produced from semiconductor wafers.

Certain semiconductor wafers are exposed to an environment that generates up to 100 possible defects per wafer. The number of defects per wafer, x, was found to follow a binomial distribution if the manufacturing process is stable and generates defects that are randomly distributed on the wafers (IEEE Transactions on Semiconductor Manufacturing, May 1995). Let p represent the probability that a defect occurs at any one of the 100 points of the wafer. For each of the following cases, dctermine whether the normal approximation can be used to characterize x.

a. p = .O1

b. p = .SO

c. p = .90