In southern California a photovoltaic (PV) system for a certain home costs $26,400 for parts and installation. This 6.3 kW system requires 340 ft? of rooftop space and has an estimated life of 16 years. a. If this PV system saves $240 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? GO a. The simple payback period for the PV system is months. (Round to the nearest whole number.)