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A new automated production process averages 2.5 breakdowns per day. Because of the cost associated with a breakdown, management is concerned about the possibility of having three or more breakdowns during a day. Assume that breakdowns occur randomly, that the probability of a breakdown is the same for any two time intervals of equal length, and that breakdowns in one period are independent of breakdowns in other periods. What is the probability of having three or more breakdowns during a day? (Round your answer to four decimal places.) Need Help? Read It Master It 5. [-/1 Points] DETAILS ASWSBE14 5.E.072. 0/2 Submissions Used MY NOTES ASK YOUR TEACHER You may need to use the appropriate appendix table or technology to answer this question. Customer arrivals at a bank are random and independent; the probability of an arrival in any one-minute period is the same as the probability of an arrival in any other one-minute period. Answer the following questions, assuming a mean arrival rate of three customers per minute. (Round your answers to four decimal places.) (a) What is the probability of exactly three arrivals in a one-minute period? (b) What is the probability of at least three arrivals in a one-minute period