Consider the problem of setting up fire stations among a group of rural commu- nities. A graph G = (V, E) is given where V is a set of communities, and two communities are adjacent if and only if a fire station from one community can reach the other community within a reasonable time. The goal is to set up a fire station in a number of communities such that all communities can be reached by some fire station within a reasonable time. We want to do so while minimizing the total number of fire stations that we set up. Formulate this problem as an integer program. Explanations are required. For example, if G is the following graph, then we can set up fire stations in 4 communities (as indicated by the grey circles)) to serve all of them. (Though it could be done with fewer fire stations.)