Answer:
So the trench is 37.5 feet wide
Step-by-step explanation:
The trench with telescope is 18 feet higher than the other.
The height of telescope is 4.5 feet.
Total height = 18 + 4.5 = 22.5
Now, we can see in the figure that the distances between telescope and the opposite trench, the height and width makes a right angled triangle.
So, perpendicular = total height = 22.5
base = wideness of the trench
We know,
Tan 31 = p/b
tan 31 = 22.5/b
b = 22.5 / 0.6
b = 37.5