Final answer:
To find the length of the bridge, we can use trigonometry and the angles of elevation provided. By using the tangent function, we can calculate the length of the bridge to be approximately 1570.84m.
Step-by-step explanation:
To find the length of the bridge, we can use trigonometry and the angles of elevation provided. Let's call the length of the bridge 'x'.
From the center of the bridge, we have a right triangle formed with the tower and the bridge. The angle of elevation of 10 degrees corresponds to the angle at the center of the bridge. Since the opposite side is the height of the tower and the adjacent side is half the length of the bridge, we can use the tangent function:
Tan(10°) = 140m / (x/2)
Simplifying, we get:
(x/2) = 140m / Tan(10°) = 785.42m
Multiplying both sides by 2, we find that the length of the bridge is approximately 1570.84m.