Waterway Firm is considering whether to outsource the manufacture of subcomponent JXY$.$ The accounting department provides the following cost information for manufacturing $11,800$ units of subcomponent JXY per month.

$\backslash$table$[[$Direct materials costs,$$38,900$

$($a$)$

Prepare an incremental analysis for subcomponent JXY$.($If an amount reduces the incremental costs then enter with a negative sign preceding the number eg$.-15,000$ or parenthesis, eg$.(15,000).$ While alternate approaches are possible, irrelevant fixed costs should be Included in both options when solving this problem.$)$