Last year Martin Motors reported the following income statement:

sales of $$21,000,000,$ cost of goods sold $60\%$ of sales, interest expense of $$2,500,000,$ preferred stock dividend of $$200,000,$ common stock dividend of $$1,650,000,$ depreciation of $$4,000,000,$ and other administrative expense of $$800,000.$ In addition, capital expenditures were $$5,000,000$ and net operating working capital increased by $$3,200,000.$ The tax rate was $40\%.$

a$.$ Find operating income for last year. According to the book, what is another name for operating income?

b$.$ Find free cash flow for last year.