I am having a hard time with this intro to finance assignment. Would someone be able to help?

Question 1: Why do we discount future value cash flows? Project 1 Year Cash Flow Discounted CF $ WACC 10% 0 1 2 3 4 5 (10,500) $ 2,000 $ 3,000 $ 4,000 $ 5,000 $ 6,000 NPV Should we do the project? Project 2 Year Cash Flow Discounted CF $ WACC 11% 0 1 2 3 4 5 (11,200) $ 3,300 $ 3,400 $ 3,500 $ 3,600 $ 3,700 NPV Should we do the project? Project 3 Year Cash Flow Discounted CF $ 12% 0 1 2 3 4 5 (21,000) $ 5,200 $ 5,400 $ 5,800 $ 6,400 $ 7,100 NPV Should we do the project? WACC Bonus 1 point 1 point 1 point 1 point Profitability Index Project PI PI rank 1 2 3 Which project is the best for our shareholders