Texas Instrument is considering a potential project. It requires an initial investment of $10 mil and is expected to last 4 years. Revenues and costs at the end of the first year are expected to be $6 mil and $2 mil, respectively. Both are expected to stay constant for the life of the project. The firm uses straight line depreciation and has 0 remaining value at the end. The working capital levels in years 1 to 4 are: $0.5 mil, $1 mil, $1.5 mil, and 0, respectively. Assume a tax rate of 35%. Calculate the free cash flow to firm (FCFF) in each of the 4 years (year 1 to year 4).

I am trying to use this formula to calculate FCFF.

FCFF = (Rev - Cost - Dep)(1 - t ) +Dep - CapExp - change in WC

where Dep=Depreciable basis * Application recovery %

I am unable to identify what is Dep and CapExp in this case. Please help!