# Airline Scheduling. Alpha Airline wishes to schedule

Airline Scheduling. Alpha Airline wishes to schedule no more than one flight out of agiven airport to each of the following cities: C, D, L, and N. The available departure slotsare 8 a.m., 10 a.m., and 12 noon. Alpha leases the airplanes at the cost of \$5000 beforeand including 10 a.m. and \$3000 after 10 a.m., and is able to lease at most two perdeparture slot. Also, if a flight leaves for location N in a time slot, there must be a flightleaving for location L in the same time slot. The expected profit (in \$1000) contributionbefore rental costs per flight is shown in the table below.Time Slot81012C1066D9109L141110N181510a) Formulate an integer linear program model that can be used to find theprofit-maximizing schedule. Define your decision variables as Xij = 1 ifa flight to destination i occurs in time slot j and Xij = 0 otherwise; and Yj= number of airplanes rented for time slot j. Write the objective functionand all the constraints.b) Use the Excel Solver to find the optimal schedule and the maximumprofit