Question

The diagram shows a 225 N load attached to a moveable pulley.What amount of force is needed to lift the load?

Answer 1

I'm happy to know that the diagram shows how it's all set up.
If I could see the diagram, then I could probably do a much
better job with an answer.  As it is ... 'flying blind' as it were ...
I'm going to wing it and hope it's somewhat helpful.

If the pulley is movable, then I'm picturing one end of the rope
tied to a hook in the ceiling, then the rope passing down through
the pulley, then back up, and you lifting the free end of the rope.

A very useful rule about movable and combination pulleys is:
the force needed to lift the load is

            (the weight of the load)
divided by
            (the number of strands of rope supporting the load) .

With the setup as I described it, there are 2 strands of rope
supporting the load ... one on each side of the pulley.  So the
force needed to lift the load is

                                 (250 N) / 2  =  125 N .