Answer
Please see the work below.
Work Step by Step
We know that
$Work \space done=mgxsin\theta$
$\implies Power\times time=mgxsin\theta$
We plug in the known values to obtain:
$350\times \frac{x}{2.22}=75\times 9.8xsin\theta$
This simplifies to:
$sin\theta=0.214$
$\theta=12.5^{\circ}$