A steel tape 30 m long, standardised at $18^{\circ} \mathrm{C}$ at a pull of 100 N was used. Find the correction per tape length, if the temperature at the time of measurement is $24^{\circ} \mathrm{C}$ and the pull exerted is 140 N . Cross-sectional area of the tape is $8 \mathrm{~mm}^2$. Take $\mathrm{E}=2 \times 10^5 \mathrm{~N} / \mathrm{mm}^2$ and $\alpha=11.2 \times 10^{-6} /{ }^{\circ} \mathrm{C}$. Tape was stretched over 4 equal spans. If measured length is 200 m , what is the actual length? Take unit weight of steel $=78.6 \mathrm{kN} / \mathrm{m}^3$.