Consider a MOS capacitor made with p-type silicon. It has an oxide thickness of $100 \mathrm{~nm}$, a fixed positive oxide charge of $10^{-8} \mathrm{C} / \mathrm{cm}^{2}$ at the oxide-silicon interface, and a metal work function of $4.6 \mathrm{eV}$. Assume that the relative permittivity of the oxide is 4 and the absolute permittivity of free space is $8.85 \times 10^{-14} \mathrm{~F} / \mathrm{cm}$. If the flatband voltage is $0 \mathrm{~V}$, the work function of the p-type silicon (in $\mathrm{eV}$, rounded off to two decimal places) is $\_\_\_\_\_\_$.