$14/15)(2$ pts$)$ A cylindrical specimen of a hypothetical metal alloy is stressed in compression. If its original and final diameters are $20\mathrm{.}000$ and $20\mathrm{.}035$ mm $,$ respectively, and its final length is $74\mathrm{.}322$ mm $,$ compute its original length if the deformation is totally elastic. The elastic and shear moduli for this alloy are $105$ GPa and $39\mathrm{.}7$ GPa $,$ respectively.