You might be referring to the white arc inside the paint underneath the basket. That's the "restricted area" if a player tries to take a charge while in that area, he will be called for a blocking foul rather than taking a charge.
area of an arc =lenght of arc *radius/2
· acute angle · algorithm · altitude · angle · area · arc · axis
A central angle can subtend (form) an arc of a circle. That has an area of 2 x pi x r x (angle A) / 360.
The area of Arc-sous-Cicon is 28.49 square kilometers.
The area of Arc-en-Barrois is 50.44 square kilometers.
The area of Arc-sous-Montenot is 10.72 square kilometers.
The area of Arc Dome Wilderness is 465.388 square kilometers.
The area of Arc-lès-Gray is 12.1 square kilometers.
The area of Bonneval-sur-Arc is 112.55 square kilometers.
The area of Arc-et-Senans is 14.98 square kilometers.
The area of Arc-sur-Tille, a commune in France, is approximately 16.08 square kilometers.