The notion of free cash flow (FCF). We defined it as EBITDA less changes in working capital less capital expenditures. There are however, other definitions of free cash flow. One is called unlevered free cash flow. It is defined as cash flow from operations PLUS interest expense MINUS capital expenditures. Another is called leveraged free cash flow. It is defined as cash flow from operations MINUS capital expenditures. Which one is more similar to our definition of free cash flow (EBITDA less changes in working capital less capital expenditures). EXPLAIN