Consider a bank with two tellers. three people, alice, betty, and carol enter the bank at almost the same time and in that order. alice and betty go directly into service while carol waits for the first available teller. suppose that the service times for each customer are exponentially distributed with mean of 4 minutes. betty finishes and leaves the bank. carol goes to the available teller. what's the probability alice leaves before carol? information is not enough 0.5 1-e(-4) e(-4) 0.25