X Company must replace one of its current machines with either Machine A or Machine B. The useful life of both machines is seven years. Machine A costs $50,000, and Machine B costs $58,000. Estimated annual cash flows with the two machines are as follows: Year von AWN- Machine A $-6,000 -8,000 -8,000 -8,000 -6,000 -5,000 -4,000 Machine B $-7,000 -4,000 -3,000 -3,000 -3,000 -2,000 -2,000 If X Company buys Machine B instead of Machine A, what is the payback period in years)