Answer:
7.48 feet
Step-by-step explanation:
To solve this question, we use this equation:
a² + b² = r²
r = 9 feet
Step 1
We find a
2a = Width of the semi circular tunnel
= 10 feet
a = 10/2
a = 5 feet
Step 2
We solve for b
b = Highest of the tunnel at the edge of the lane
a² + b² = r²
5² + b² = 9²
b² = 9² - 5²
b = √81 - 25
b = √56
b = 7.4833147735 feet
Therefore, rounding off to 2 decimal places, the height of the tunnel at the edge of each lane is 7.48 feet