In a photoelectric effect experiment, a metal sample is illuminated by 10.0 mW of ultraviolet light of wavelength 240 nm. It is observed that 250,000 photoelectrons are ejected from the metal each second, with kinetic energies from zero to 2.20 eV.
1. What is the work function of this metal, in eV?
2. What is the longest wavelength of light that can knock electrons out of this metal?