the manager of a grocery store in decatur currently provides special service to people who still use checks to pay for food. they have a separate pay/bag line for people who insist on waiting for a dollar total to pull out their checkbook and start writing. on average, 30 customers per hour arrive at the checking pay/bag line and they can be modeled with a poisson distribution. the clerk at this line can handle an average rate of 35 customers per hour and their service can be modeled with exponential distribution.