Question

A levelling is a carried out to establish the Reduced Level (RL) of a point C with respect to Bench Mark (BM) at A. The staff reading taken are given below.

Staff station	BS (m)	IS (m)	FS (m)	RL (m)
A	1.545	-		100.00
B	-0.860	-	-1.420
C		-	0.835

If RL of A is 100.00 m, then RL of C is

• A. 102.105 m
• B. 102.965 m
• C. 100.84 m
• D. 101.27 m

Answer 1

The correct option is D 101.27 m

HI = RL + BS
and RL = HI - BS

Staff station	BS (m)	IS (m)	FS (m)	HI (m)	RL (m)
A	1.545	-		101.545	100
B	-0.860	-	-1.420	102.105	102.965
C	-	-	0.835	-	101.27

$\therefore$ RL of C = 101.27 m