A steel cable with nominal diameter $25 \mathrm{mm}$ (see Table $2-1$ ) is used in a construction yard to lift a bridge section weighing $38 \mathrm{kN},$ as shown in the figure. The cable has an effective modulus of elasticity $E=140 \mathrm{GPa}$
(a) If the cable is $14 \mathrm{m}$ long, how much will it stretch when the load is picked up?
(b) If the cable is rated for a maximum load of $70 \mathrm{kN}$ what is the factor of safety with respect to failure of the cable?