Consider the semiconductor wafer data in Table 2-1. Suppose that 10 wafers are selected randomly (without replacement) for an electrical test. Determine the following:

(a) Probability that exactly 4 wafers have high contamination.

(b) Probability that at least 1 is from the center of the sputtering tool and has high contamination.

(c) Probability that exactly 3 have high contamination or are from the edge of the sputtering tool.

(d) Instead of 10 wafers, what is the minimum number of wafers that need to be selected so that the probability that at least 1 wafer has high contamination is greater than or equal to 0.9?