a) A beam of light with intensity of 3 mW and a wavelength of 743 nm is striking a solar cell. Estimate the number of photons incident on the cell. b) If the dark saturation current of a solar cell is 1.7X10-9 A/m, the cell temperature is 27 C, and the short- circuit current density is 250 A/m, calculate the open-circuit voltage, Voc; voltage at maximum power, Vmax; current density at maximum power, Imax; maximum power, Pmax; and maximum efficiency, Nmax. What cell area is required to get an output of 20 W when the available solar radiation is 820 W/m