Please explain me the procedure

The owner of a small deli is trying to decide whether to discontinue selling magazines. He suspects that only 7.2%% of his customers buy a magazine and he thinks that he might be able to use the display space to sell something more profitable. Before making a final decision, he decides that for one day he will keep track of how many of the first 14 customers buy a magazine. (a) Explain why this is a binomial experiment. (b) Assuming his suspicion that 7.2% of his customers buy a magazine is correct, what is the probability that exactly 4 out of the first 14 customers buy a magazine? Give your answer as a decimal number rounded to two digits. (c) What is the expected number of customers from this sample that will buy a magazine