Construction Inc is considering to invest in $3$ projects. Here are the details:

Year $0=$ initial investment

Year $1-4=$ Cash inflows

Year $0$ Year $1$ Year $2$ Year $3$ Year $4$

Project A $(1,000)400400400400$

Project B $(1,000)600500300200$

Project C $(1,000)200300500600$

Required:

a$.$ Calculate IRR & NPV and recommend which project will be a good investment and which project will be a bad investment and why. Assume $20\%$ cost of capital.