Edexcel A-Level Physics Gravitational Potential Energy

The diagram shows a system used to move a stone block up a ramp. A team of people uses a rope to pull the block at a constant speed.

height of ramp $=4.35 \mathrm{~m}$
angle of ramp to horizontal $=6.0^{\circ}$
mass of block $=2.10 \times 10^{3} \mathrm{~kg}$
speed of block up ramp $=0.450 \mathrm{~m} \mathrm{~s}^{-1}$
total power of team $=6.25 \mathrm{~kW}$

Show that the useful work done on the block is about 90 kJ.