Answer:
W = 3.4x0³ J.
Step-by-step explanation:
The work done by the man is given by the following equation:
(1)
where W: is the work, Ft is the total force and d: is the displacement = 4.25 m.
We need to find first the total force Ft, which is:

where Fm: is the force exerted by the man = 535 N, W: is the weight = m*g*sin(θ), m: is the mass of the man, g: is the gravitational acceleration = 9.81 m/s², and θ: is the angle = 20.0°.

Hence, the work is:
Therefore, the work done by the man is 3.4x10³ J.
I hope it helps you!