A laser pointer sends out 5.0 mW of red light of wavelength 650 nm…

Step 1. One photon. $E = \dfrac{1240\ \text{eV nm}}{650\ \text{nm}} = 1.91\ \text{eV} = 1.91 \times 1.6 \times 10^{-19}\ \text{J} = 3.05 \times 10^{-19}\ \text{J}$.

Step 2. Photons each second. $P = 5.0 \times 10^{-3}$ W, so $N = \dfrac{P}{E} = \dfrac{5.0 \times 10^{-3}\ \text{W}}{3.05 \times 10^{-19}\ \text{J}} = 1.64 \times 10^{16}\ \text{s}^{-1}$.

Step 3. Electrons each second. $0.0020 \times 1.64 \times 10^{16}\ \text{s}^{-1} = 3.28 \times 10^{13}\ \text{s}^{-1}$.

Step 4. The current. $I = 3.28 \times 10^{13}\ \text{s}^{-1} \times 1.6 \times 10^{-19}\ \text{C} = 5.24 \times 10^{-6}\ \text{A} = 5.24\ \mu\text{A}$.