You are given the following information for Smashville, Inc.

Cost of goods sold:	$229,000
Investment income:	$2,500
Net sales:	$374,000
Operating expense:	$82,000
Interest expense:	$7,400
Dividends:	$9,000
Tax rate:	21	%

Current liabilities:	$18,000
Cash:	$21,000
Long-term debt:	$23,000
Other assets:	$41,000
Fixed assets:	$166,000
Other liabilities:	$5,000
Investments:	$45,000
Operating assets:	$37,000

Calculate the gross margin, the operating margin, return on assets, and return on equity.