Below are the revenues and cost data from King Clothes

Sales Revenue		$550.000
Cost of Goods Sold (40% of sales revenue)		185000
Gross Profit		365000
Operating Costs:(?)
Salaries fixed	150000
Sales commissions (15%of sales)	65250
Depreciation of equipment and fixtures	15000
Insurance for the year	5000
Store rent ($5000 per month)	45000
Other operating costs	65000	345250
Operating income (loss)		19750

The total other operating cost amounted to $65,000 consists of 60% of variety of sales cost and 40% of cost that is unrelated with sales.

Determine:

a. Contribution margin and contribution margin percentage. b. King estimates that if she could spend an additional $16,500 on sales promotions, the revenue could increase by 25%. What should be King's decision?