Mr A B and C are trying to put a heavy Piston into a cylinder at mechanical workshop in Railway Yard if they apply forces f1, f2 and f3 respectively on ropes then for which set of forces at that instant will be able to perform the said job

In this question please take all the components along the direction of the force applied by Mr.C , now the component of the force F1 that is being applied Mr A is opposite to that of B & C so subtract it from the forces of Mr Bi.e from the component of that force along horizontal direction and from C which is already in horizontal direction or vice versa.
sin60^​oF1-cos60^oF2-F3
Now, 
Sin60⁰F1=cos60^OF2+ F3
Now put the values of sin and cos in their respective places you will surely get your answer. Hope it would help if anything is wrong pls forgive iam also a student not an expert. Thankyou