A point charge of $10^{-8} \text{ C}$ is placed at origin. The work done in moving a point charge $2 \text{ \mu C}$ from point $A(4, 4, 2) \text{ m}$ to $B(2, 2, 1) \text{ m}$ is ________ $J$. $(\frac{1}{4\pi\epsilon_0} = 9 \times 10^9 \text{ in SI units})$