Consider two digital fuel pumps A and B that could be used in a single gas station. Pump A has a mean effective process time of 4 minutes with squared-coefficient of variation of 0.5. Pump B has a mean effective time of 3 minute with squared-coefficient of variation of 5.

Assume that the arrival rate of cars is 0.2 car per minute with squared-coefficient of variation of 1. Which pump will have a longer average cycle time? (Hint: the number of machines, m, is 1.) (20 Points)

(Pump A) te: ______ ce2: ______ ra: ______ ca2: ______u:______ CTq: ______ CT: ______

(Pump B) te: ______ ce2: ______ ra: ______ ca2: ______ u: ______ CTq: ______ CT: ______

(a) Now assume that the number of pumps in the gas station could be two (two pumps of A or two pumps of B). What will happen to cycle time if the arrival rate of cars is doubled? (20 Points)

(Pump A) te: ______ ce2: ______ ra: ______ ca2: ______u: ______ CTq: ______ CT: ______

(Pump B) te: ______ ce2: ______ ra: ______ ca2: ______ u: ______ CTq: ______ CT: ______

(a) Again, assume that there could be only one pump in the gas station like Part a. If the arrival rate increases to 0.24 cars, what will happen to the cycle time? Compare with Part a. (20 Points)

(Pump A) te: ______ ce2: ______ ra: ______ ca2: ______u: ______ CTq: ______ CT: ______

(Pump B) te: ______ ce2: ______ ra: ______ ca2: ______ u: ______ CTq: ______ CT: ______