Needs to be solved in AMPL!!

9-21. Washington County includes six towns that need emergency ambulance service. Be- cause of the proximity of some of the towns, a single station may serve more than one community. The stipulation is that the station must be within 18 minutes of driving time from the towns it serves. The table below gives the driving times in minutes among the six towns. Time in minutes from i toj 1 2 3 4 5 6 1 2 3 4 5 6 0 19 23 18 20 19 0 22 13 22 11 23 18 22 13 0 60 60 0 17 55 2017 20 25 22 11 17 20 55 17 0 12 120 25 | Formulate an ILP whose solution will produce the smallest number of stations and their locations. Find the optimum solution