The manufacturing of semiconductor chips produces 2% defective chips. Assume that the chips are independent and that a lot contains 1000 chips. Round your final answers to three decimal places

(e.p. 98.765). (a) Approximate the probability that more than 25 chips are defective. (b) Approximate the probability that between 20 and 30 chips are defective. (Use Appendix A, Table I. Also apply the Va correction factor and round value of standard normal random variable to 2 decimal places.)