Duke Inc. recently reported $13,750 of sales, $5,500 of operating costs other than depreciation, and $1,250 of depreciations. The company had $3,500 of bonds that carry a 6.25% interest rate, and its federal-plus-state income tax rate was 35%. during the year, the firm had expenditure on fixed assets and increase in net operating working capital that totaled $1,550,which support the firm's operations and future growth. What was its free cash flow?

A) 4,250

B) 4,350

C) 4,400

D) 4,450