Here is the answer, but I don't know how to solve dollar amount and company B's percentage. Please provide solution for me thanks :)

	Company A			Company B			Company C
Sales......................................	$400,000	*		$750,000	*		$600,000	*
Operating income.....................	$32,000			$45,000	*		$24,000
Average operating assets..........	$160,000	*		$250,000			$150,000	*
Return on investment (ROI).......	20%	*		18%	*		16%
Minimum required rate of return:
Percentage...........................	15%	*		20%			12%	*
Dollar amount.......................	$24,000			$50,000	*		$18,000
Residual income.......................	$8,000			($5,000)			$6,000	*

EXERCISE 11-8 Return on Investment and Residual Income Relationships LO3, LO4] family friend has asked for your help in analyzing the operations of three companies operating in the same service sector industry. Supply the missing data in the following table Company Sales $400,000 $150,000 $600000 Operating income 45,000 $150000 $160000 Return on investment 20% 18% Minimum required rate of return Percentage 15% Dollar amount. 50,000 6000 Residual income