Multiply the obtained pool water area by the average depth, which is equal to the pool water volume.
The formula of sector area, specifically, sector area S= angle of central angle (angle system) × pi 3. 14× radius r _/360.
A figure surrounded by an arc and two radii passing through both ends of the arc is called a fan (the combination of a semicircle and a diameter is also a fan). Obviously, it is surrounded by a part of the circumference and its corresponding central angle.