A system costs $ 10,000 and has the potential to save $ 4,000 a year in electricity costs at the health food store. If the store owner applies an interest rate of 20% for this type of investment and accepts only those projects that meet a 4-year discounted payback. Determine how much this value would be. Round to the next integer.

a. No correct answer is provided. b. 5 c. 4 d. No correct answer is provided. and. 3