A spare parts seller finds that 3 in every 100 parts sold is defective. Find the probability that

(a) the first defective part is the eighth part sold,

(b) the first defective part is the first, second or third part sold,

(c) none of the first 8 parts sold are defective.

Find the indicated probabilities using the geometric distribution, the Poisson distribution, or the binomial distribution. Then determine whether the events are unusual. If convenient, use a table or technology to find the probabilities.