Need the calculation steps and explain. THANKS :)

Sales COGS Interest Dividends Depreciation Cash Receivables Current liabilities Inventory Long-term debt Net fixed assets Tax rate 2014 $2,900 2,030 410 56 290 250 242 900 1,015 3,200 6,000 34% 2015 $3,300 2,310 420 79 330 150 412 1,100 900 3,100 5,700 34% What is operating cash flow for 2015