Here- 1. For initial investment if we have deducted salvage value of machinery once, why are we again deducting the same in terminal flow?   Why is same thing being done twice?

Here- 1. In initial investment we are deducting post salvage value of machinery.   2. Also we in terminal flow are deducting post salvage value foregone. Why is this done twice if once salvage value is considered

Sir how shall this be solved using the calculator?

Here for finding out present value why is 14% instead of 12% and how to know when to take which rate of interest?