In a year of rising costs and prices, the firm reported net income of 480,000 and average assets 3,600,000. If Natco had used the LIFO cost-flow assumption in the same year, its cost of good sold would have been $80,000 more than under FIFO, and its average assets would have been $80,000 less than under FIFO. Calculate the firm's ROI under each cost-flow assumption.