To determine the elevation of the top Q of a signal on a hill, observations were made from two points P and R. all three points are in the same vertical plane.
The angle of elevation to Q
From P = 25o 35’, From R = 15o 5’
Staff reading at BM
From P = 2.755 m, From R = 3.855 m
R.L of B.M = 105.42 m
The distance between P and R is 120 m, and the height of the signal is 4 m. Find out the R.L. of the foot of the signal.
Enter numerical value using the virtual keypad. Round off where necessary.