Answer:
Length of the drain pipe is 72.15 feet.
Explanation:
From the figure attached,
A drain pipe is to be laid between two pints P and Q.
Point P is 15 ft higher than the other point Q.
Angle of elevation of point P from point Q is 12°.
Let the length of pipe is l feet.
By applying Sine rule in the given right triangle PRQ,
Sin(∠Q) =

Sin(12) =

0.20791 =



l = 72.15 ft
Therefore, length of the drain pipe is 72.15 feet.