An aircraft maintenance base has the resources to check only one aircraft engine at a time. Therefore, to return the planes as soon as possible, the policy that is followed is to postpone the review of the 4 engines of each plane. In other words, only one engine of the plane is checked every time a plane arrives at the base. With this policy, the planes arrive according to a Poisson distribution of average rate one per day. The time required to check an engine (once the work begins) has an exponential distribution of an average 1/2 day. A proposal has been made to change the review policy so that the 4 engines are reviewed consecutively every time a plane arrives at the base. Although this would quadruple the expected service time, each plane would need to be checked only with a frequency, 4 times less. Use the queue theory to compare the 2 alternatives.