Traditional payback period-discount payback period

Question

Project K has a cost of $52,125 and its expected net cash inflows are $12,000 per year for eight years. The firm's a rate of return is 12 percent. Compute the project's

(a) traditional payback period (PB)

(b) discount payback period ( DPB)

(c) net present value (NPV)

(d) internal rate of return.