Bunker Hill Mining Company has two competing proposals: a processing mill and an electric shovel. Both pieces of equipment have an initial investment of $577,728. The net cash flows estimated for the two proposals are as follows: The estimated residual value of the processing mill at the end of Year 4 is $250,000. The estimated residual value of the processing mill at the end of Year 4 is $250,000. Present Value of $1 at Compound Interest table appearing above