A light of wavelength 332 nm falls on the surface of potassium, which has a work function of 2.26 eV. Find the maximum speed of photoelectrons emitted from the surface. (In order to avoid rounding errors, let h = 6.626 10-34 J · s, me = 9.11 10-31 kg, and 1 eV = 1.6 10-19 J.)