The five nodes in the following network represent points one year apart over a four-year period. Each node indicates a time when a decision is made to keep or replace a tirm's computer equipment. If a decision is made to replace the equipment. a decision must also be made as to how long the new equipment will be used. The are from node 0 to node 1 represents the decision to keep the current equipment one year and replace it at the end of the year. The are from node 0 to node 2 represents the decision to keep the current equipment two years and replace it at the end of year 2. The numbers above the arcs indicate the total cost associated with the equipment replacement decisions. These costs include discounted purchase price. trade-in value. operating costs. and maintenance costs. Use linear programming (NOT lshortestroute model) to determine the minimum cost equipment replacement policy for the four-year period. ' '