Companion Computer Company has been purchasing carrying cases for its portable computers at a delivered cost of $59 per unit. The company, which is currently operating below full capacity, charges factory overhead to production at the rate of 36% of direct labor cost. The fully absorbed unit costs to produce comparable carrying cases are expected to be as follows:

Direct materials	$27.00
Direct labor	16.00
Factory overhead (36% of direct labor)	5.76
Total cost per unit	$48.76

If Companion Computer Company manufactures the carrying cases, fixed factory overhead costs will not increase and variable factory overhead costs associated with the cases are expected to be 14% of the direct labor costs.

a. Prepare a differential analysis, dated October 11, 2014, to determine whether the company should make (Alternative 1) or buy (Alternative 2) the carrying case. If required, round your answers to two decimal places. If an amount is zero, enter zero "0".

	Make carrying case (alt 1)	buy carrying case (alt 2)	differential analysis
purchase price	0	59	-59
direct materials per unit	27	0	27
direct labor per unit	16	0	16
variable factory overhead per unit	2.24	0	2.24
fixed factory overhead per unit	???	????	0
income (loss)	??	??	-13.76

I can't figoure out how to get the areas with the question marks. Please help! Can someone explain it to me?