Refer to the diagram shown below.
The diameter of the semi-circular arch is 15 yards, and its radius is 7.5 yards.
Calculate the area of the cross-section (a rectangle and a semicircle).
A = (15)(5) + (1/2)*π*(7.5²)
= 75 + 0.5*3.14*56.25
= 163.3125 yd²
The volume is the area times the length.
The volume is
V = 163.3125*30
= 4899.375 yd³
Answer: 4899.38 yd³ (nearest hundredth)
