You are given the following information for Smashville, Inc.

Cost of goods sold:	$179,000
Investment income:	$1,500
Net sales:	$364,000
Operating expense:	$78,000
Interest expense:	$7,400
Dividends:	$12,000
Tax rate:	21	%

Current liabilities:	$18,000
Cash:	$21,000
Long-term debt:	$45,000
Other assets:	$39,000
Fixed assets:	$160,000
Other liabilities:	$4,000
Investments:	$35,000
Operating assets:	$64,000

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