A vertical post 18 feet high is broken at a certain height and its upper part, not completely separated, meets the ground at an angle of 30°. Find the height (in feet) from the ground at which the post is broken.

Two points, A and B, are given. If the Reduced Level (RL) of point A is 100.00 m, find the difference in RL between A and B given that the back sight to A is 2.0 m and the fore sight to B is 1.5 m.

A 24 m long ladder is leaning against a wall. If the ladder makes an angle of 30° with the wall, what is the distance (in m) of the foot of the ladder from the wall?