The following information ($ in millions) comes from a recent annual report of Amazon.com, Inc.: Net sales $ 10,712 Total assets 4,374 End of year balance in cash 1,212 Total stockholders' equity 495 Gross profit (Sales Cost of Sales) 2,538 Net increase in cash for the year 27 Operating expenses 2,066 Net operating cash flow 704 Other income (expense), net (16) Compute Amazon's total liabilities at the end of the year.