In southern California a photovoltaic (PV) system for a certain home costs $16,500 for parts and installation. This 5.6 kW system requires 360 ft of rooftop space and has an estimated life of 15 years. a. If this PV system saves $150 each month in electricity expenses, what is the simple payback period in months? b. If the market value of the PV system is negligible, what is the system's IRR? a. The simple payback period for the PV system is months. (Round to the nearest whole number.) b. The IRR of the PV system is % per month. (Round to one decimal place.)