An angler hangs a fish of mass m from a vertical steel wire of length l and in cross- sectional area a. the upper end of the wire is securely fastened to a support. (a) calculate the amount the wire is stretched by the hanging fish. (b) the angler now applies a varying force f⃗ at the lower end of the wire, pulling it very slowly downward by δ from its equilibrium position. for this downward motion, calculate the work done by gravity. (c) for this downward motion, calculate the work done by the force f⃗. (d) calculate the work done by the force the wire exerts on the fish. (e) calculate the change in the elastic potential energy (the potential energy associated with the tensile stress in the wire).