Example $2-10$

A steel tape is standardized at $68F$ under a tension of $15lb$ when supported at the two ends only, and the distance between the zero mark and the $100-ft$ mark is $99\mathrm{.}972ft.$ The total weight of the tape is $2\mathrm{.}80lb,$ and its cross$-$sectional area is $0\mathrm{.}0088i{n}^2$ For steel $E$ is assumed to be $30,000,000.$ What is the distance between

the zero and $100-$ft marks when the tape is supported at the two ends only, the tension is $25lb,$ and the standard temperature prevails?