Question: Vehicle Routing. Consider the dispatching of delivery vehicles (for example, mail trucks, fuel-oil trucks, newspaper delivery trucks, etc.). Typically, there is a fleet of vehicles that must be routed to deliver goods from a depot to a given set of n drop-points. Given a set of feasible delivery routes and the cost associated with each one, explain how to formulate the problem of minimizing the total delivery cost as a set-partitioning problem.