Consider a cylindrical cable with a hanging weight suspended from it$.$

When the mass is removed, the length of the cable is found to be l$0=4\mathrm{.}6$ m$.$ After the mass is added, the length is remeasured and found to be l$1=5\mathrm{.}44$ m$.$ Determine Young's Modulus Y in N$/$m$2$ for the steel cable if the weight has a mass m $=75$ kg and the cable has a radius r $=0\mathrm{.}035$ m$.$

If this cable is pulled down a distance d in m from its equilibrium position it acts like a spring when released. Write an expression determining the spring constant k of this material using the cable$-$specific variables Y $,$ l$1,$ l$0,$ and r provided in part A$.$