Use dynamic programming (graphical approach) to find the optimal inventory policy and minimum total cost for the following four-month deterministic inventory problem. The cost and demand data are provided in the table below. Note that the setup cost, unit production cost, and unit holding cost change from period to period. The initial inventory is zero, but it is required to have a final inventory of 5 units at the end of the fourth month. In case of a tie, provide all optimal policies