In 2011, Ross corporation had year-end assets of $550,000, sales of $790,000, net income of $90,000, net cash flows from operating activities of 180,000, purchases of plant assets of $120,000, and sales of plant assets of $20,000, and it paid dividends of $40,000. In 2010, year end assets were $500,000. Calculate the cash-generating efficiency ratios of cash flow yield, cash flows to sales, and cash flow to assets. Also calculate free cash flow.