Chapter 30 - Current and Resistance - Exercises and Problems - Page 887: 2

$ v_d = 1.02* 10^{-14} m/s$

We have $ i = \frac{q}{t}$ $ i = \frac{n_e*e}{t}$ $ i = \frac{n_e*e}{5}$ also we have $i = n_e*A*v_{d}$ $\implies i = \frac{n_e*e}{5} = n_e*A*v_d$ $\implies \frac{e}{5} = A* v_d$ $\implies v_d = \frac{e}{5* \pi*r^2}$ $\implies v_d = \frac{1.6*10^{-19}}{5* 3.14*(10^{-3})^2} m/s$ $\implies v_d = 1.02* 10^{-14} m/s$