The president of Hill Enterprises, Terri Hill, projects the firm's aggregate demand requirements over the next $8$ months as follows:

$\backslash$table$[[$January$,1,500,$May,$2,300],[$February$,1,600,$June,$2,200],[$March$,1,700,$July,$1,900],[$April$,1,700,$August,$1,300]]$

is $$20$ per unit per month. Ignore any idle$-$time costs. The plan is called plan B$.$ capacity is limited to $1,000$ units per month. Evaluate this plan by computing the costs for January through August.

$\backslash$table$[[$Period$,$Month,Demand,Production,$\backslash$table$[[$Ending$],[$Inventory$]],\backslash$table$[[$Subcontract$],[$Units$]]],[0,$December,,,$200,],[1,$January,$1,500,1,300,,],[2,$February,$1,600,1,300,,],[3,$March,$1,700,1,300,=,],[4,$April,$1,700,1,300,,],[5,$May,$2,300,1,300,,],[6,$June,$2,200,1,300,,],[7,$July,$1,900,1,300,-,],[8,$August,$1,300,1,300,,]]$