Answer
The force of the rope does work on the skier at a rate of $~~225~W$
Work Step by Step
At a speed of $2.0~m/s$, the skier takes $4.0~s$ to move $8.0~m$
We can find the rate at which the force of the rope does work on the skier:
$P = \frac{W}{t} = \frac{900~J}{4.0~s} = 225~W$
The force of the rope does work on the skier at a rate of $~~225~W$.