Keeping the instrument height as 1 m, length of staff 4 m, the up gradient of the ground 1 in 10, the sight on the up slope must be less than

If you know the elevation of A, called E(A), you can calculate the elevation of B, called E(B), as BS -FS + E(A). But BS + E(A) = HI, the height of the instrument or the elevation of the line of sight directed from the level.