Customers arrive at a bank according to a Poisson process with a rate customers per hour.

A). What is the expected time of k-th customer's arrival?

B). Suppose customer are waiting in line an hour before the bank opens, and the queue's capacity is 3. What is the probability that the queue will be full? Write down the expression.

C). What is the probability that 1 arrives within 1 hour, given that a total of 5 arrives within 3 hours?

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