A particular telephone number is used to receive both voice calls and fax messages. Suppose that 25% of the incoming calls involve fax messages, and consider a sample of 25 incoming calls. (Round your answers to three decimal places.)
(a) What is the probability that at most 7 of the calls involve a fax message?
(b) What is the probability that exactly 7 of the calls involve a fax message?
(c) What is the probability that at least 7 of the calls involve a fax message?
(d) What is the probability that more than 7 of the calls involve a fax message?