solve this question by hand and excel. explain the each step of solution

SmartMart sells three models of couches, the Single, the Double, and the L-shaped. Annual demands for the three products are S = 2,000, D = 1,200 and L = 500 units. Each model costs the company $1000. A fixed transportation cost of $2,000 is incurred each time an order is delivered. For each model ordered and delivered on the same truck, an additional fixed cost of $500, $600 $700 are incurred for S, D and L respectively. SmartMart incurs a holding cost of 25 percent. a) Evaluate the lot sizes that the manager should order if lots for each product are ordered and delivered independently. b) Evaluate the annual cost of such a policy. SmartMart sells three models of couches, the Single, the Double, and the L-shaped. Annual demands for the three products are S = 2,000, D = 1,200 and L = 500 units. Each model costs the company $1000. A fixed transportation cost of $2,000 is incurred each time an order is delivered. For each model ordered and delivered on the same truck, an additional fixed cost of $500, $600 $700 are incurred for S, D and L respectively. SmartMart incurs a holding cost of 25 percent. a) Evaluate the lot sizes that the manager should order if lots for each product are ordered and delivered independently. b) Evaluate the annual cost of such a policy