A light wave described by $E = 60[\sin(3 \times 10^{15})t + \sin(12 \times 10^{15})t]$ (in SI units) falls on a metal surface of work function $2.8 \text{ eV}$. The maximum kinetic energy of ejected photoelectron is (approximately) ________ $\text{eV}$. ($h = 6.6 \times 10^{-34} \text{ J-s}$ and $e = 1.6 \times 10^{-19} \text{C}$)