nterspace Merchandising anticipated selling $29,000$ units of a major product and paying sales commissions of $$6$ per unit. Actual sales and sales commissions totaled $31,500$ units and $$182,700,$ respectively. If the company used a static budget for performance evaluations, Interstate would report a cost variance of: $$6,300$U$.$ $$6,300$F$.$ $$8,700$U$.$ $$8,700$F$.$ some other amount not listed above.

The correct answer is apparently $8000$ F$,$ please demonstrate how that is the case.