A block of mass $m = 2.0 \text{ kg}$ is initially at rest on a frictionless horizontal floor. At $t = 0$, a constant horizontal force of $F = 6.0 \text{ N}$ is applied to the block in the $+x$ direction. The force is applied for a duration of $t = 4.0 \text{ s}$ and then removed. An observer runs past the block with a constant velocity of $v = 8.0 \text{ m/s}$ in the $+x$ direction. In this observer's inertial reference frame, what is the total work done by the force on the block?