A metal has a work function of 2.75 eV. Ultraviolet light of 350 nm falls on it.

Step 1. The photon. $E = \dfrac{1240\ \text{eV nm}}{350\ \text{nm}} = 3.54\ \text{eV}$.

Step 2. Einstein. $KE_{\max} = 3.54\ \text{eV} - 2.75\ \text{eV} = 0.79\ \text{eV}$.

Step 3. The stopping potential. $eV_0 = 0.79\ \text{eV}$, so $V_0 = 0.79\ \text{V}$.