Alamal hospital is considering the purchase of a new exercise machine at cost of $21000. It should save $6000 in cash operating cost per year. Its estimated useful life is 5 years, and will have$ 1000 disposal value, but expected to be sold for 2000$. Required; 1. Compute the payback time? 2. Compute the net present value of the proposal and put your suitable recommendation regarding its implementation (discount rate=10%)