Answer
The rope does $3120~J$ of work on the sled.
Work Step by Step
We can find the distance the sled moves in $10.0~s$:
$d = v~t = (1.5~m/s)(10.0~s) = 15.0~m$
We can find the work done by the rope:
$Work = F~d~cos~\theta$
$Work = (240~N)(15.0~m)~cos~30.0^{\circ}$
$Work = 3120~J$
The rope does $3120~J$ of work on the sled.
