Seventy percent of the bicycles sold by a certain store are mountain bikes. Among 100 randomly selected bike purchases, find the probabilities below. (Round all answers to four decimal places.) (a) What is the approximate probability that at most 80 are mountain bikes? in (b) What is the approximate probability that between 60 and 80 (inclusive) are mountain bikes? (c) What is the approximate probability that more than 85 are mountain bikes? (d) What is the approximate probability that at most 30 are not mountain bikes?