A theodolite is set up at station $A .$ The $R L$ of instrument axis is $212.250 \mathrm{~m}$. The angle of elevation to the top of a $4 \mathrm{~m}$ long staff, held vertical at station $\mathrm{B},$ is $7^{\circ} .$ The horizontal distance between stations $\mathrm{A}$ and $\mathrm{B}$ is $400 \mathrm{~m} .$ Neglecting the errors due to curvature of earth and refraction, the RL (in $\mathrm{m},$ round off to three decimal places $)$ of station $\mathrm{B}$ is

A theodolite is set up at station $A .$ The $R L$ of instrument axis is $212.250 \mathrm{~m}$. The angle of elevation to the top of a $4 \mathrm{~m}$ long staff, held vertical at station $\mathrm{B},$ is $7^{\circ} .$ The horizontal distance between stations $\mathrm{A}$ and $\mathrm{B}$ is $400 \mathrm{~m} .$ Neglecting the errors due to curvature of earth and refraction, the RL (in $\mathrm{m},$ round off to three decimal places $)$ of station $\mathrm{B}$ is

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