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28 percent of all customers who enter a store will make a purchase. Suppose that 6 customers enter the store and that these customers make independent purchase decisions. Required: \begin{tabular}{|l|l|} \hlinen & p \\ \hline & \\ \hline \end{tabular} a) Calculate the probability that exactly five customers make a purchase. b) Calculate the probability that at least three customers make a purchase. c) Calculate the probability that two or fewer customers make a purchase. d) Calculate the probability that at least one customer makes a purchase. e) Calculate the expected number of customers that make a purchase