During a differential leveling survey between BM $200$ and BM $300,$ the surveyor finds that the total of the backsight $($BS$)$ readings are $40\mathrm{.}20$ feet and the total of the foresight $($FS$)$ readings are $35\mathrm{.}83$ feet. If the elevation of the benchmark used $($BM $200)$ is $150\mathrm{.}00$ feet, what is the elevation of the BM $2?$

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