4. Each item produced by a certain manufacturer is, independently, of acceptable quality with probability 0.95. Suppose that we want to approximate the probability that at most 10 of the next 150 items produced are unacceptable. a) Approach this using the normal approximation to the binomial distribution. Make sure to provide a z-score and a probability with four decimal places. b) Use either R or the Excel BINOM.DIST function to find the exact probability.