The manager of a market can hire either mary or alice. mary, who gives service at an exponential rate of 25 customers per hour, can be hired at a rate of $4 per hour. alice, who gives service at an exponential rate of 30 customers per hour, can be hired at a rate of $c per hour. the manager estimates that, on the average, each customer’s time is worth $1 per hour and should be accounted for in the model. assume customers arrive at a poisson rate of 10 per hour (a) what is the average cost per hour if mary is hired? if alice is hired? (b) find c if the average cost per hour is the same for mary and alice.