How to calculate operating cash flow? Is the formula: operating cash flow= net sales- cost of goods- tax always right?

Calculating Cash Flows [L02] Quarles Industries had the following operating results for 2015:sales = $30,096; cost of goods sold = $21,476; depreciation expense = $5,341; interest expense. = $2,409; dividends paid = $1,716. At the beginning of the year, net fixed assets were $18,018, current assets were $6,336, and current liabilities were $3.564. At the end of the year, net fixed assets were $22,176, current assets were $7,829, and current liabilities were $4,159. The tax rate for 2015 was 35 patent. a. What is net income for 2015? b. What is the operating cash flow for 2015? c. What is the cash flow from assets for 2015? Is this possible? Explain. d. If no new debt was issued during the year, what is the cash flow to creditors? What is the cash flow to stockholders? Explain and interpret the positive and negative signs of your answers in (a) through (d).