1500 cubic feet water is needed to fill the tank. Option B.
Explanation:
Given,
The diameter of the cylindrical water tank is 20 ft.
So, the radius (r) = 10 ft
Height (h) = 15 ft
To find the water to be filled in the tank we need to find out the volume.
Formula
volume of cylinder (V) = πr²h
Now,
Putting the values of r and h in the given formula we get,
V = π×10²×15 = 1500π cubic feet
Hence,
1500 cubic feet water is needed to fill the tank.