Payback period and accounting rate of return: Equal annual operating cash flows with disinvestment

Khazanchi in considering an investment proposal with the following cash flows

Initial investment-depreciable assets	$100,000
Initil investments-working capital	12,500
Net cash inflows from operations (per year for 8 years)	25,000
Disinvestment-depreciable assets	10,000
Disinvestment-working capital	12,500

A) Determine the payback period

B) Determine the accounting rate of return on initial investment

C) Determine the accounting rate of return on average investment