Which one is correct if the deflection of a beam is y

Bending moment at any section in a conjugate beam gives in the actual beam:

In a pin jointed plane frame all the loads are assumed to act

The bending moment is maximum on a section where shear force

According to Hook's law, which one is wrong ?

Toughness is

A pin jointed frame with with J number of joints and n, number of members will be a perfect frame if

The displacements of joints of a truss can be obtained directly from

The stiffness method in structural analysis is also known as: