Oahu Inc. is considering an investment in new equipment that will be used to manufacture a smartphone. The phone is expected to generate additional annual sales of 5,800 units at $294 per unit. The equipment has a cost of $593,300, residual value of $44,700, and an 8 -year life. The equipment can only be used to manufacture the phone, The cost to manufacture the phone follows: Determine the average rate of return on the equipment. If required, round to the nearest whole percent. %