no wait..the incremental revenues are 40000..and the incremental costs are 7500, and the loss due to commission is 12000 so that gets subtracted ...it comes out to be 20500
and it's earning 12000 ...before..when it outsources the work..when it acquires the machine..there's a loss of 12000 since it won't be earning that..so 12000 will get subtracted..not added..
And you can't assume a tax rate, because it says 'net of taxes', which implies that tax has been adjusted from everything and what is left are the real cash flows which need to be calculated