Dynamic Programming 9. 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 firm's com- puter 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 I rep- resents the decision to keep the current equipment one year and replace it at the end of the year. The arc 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 cost associated with the equipment replacement dec purchase price, trade-in value, operating costs, and maintenance costs. Determine the mini mum cost equipment replacement policy for the four-year period the total costs include discounted isions. These 2000 1000 200 800 500 1600