   
Circle Semicircle Arc Sector Quadrant Segment
1.    :−
  = 
   =
1
2

   =
(
−
)
()   =2
   = 
    =  +
   =
360
×
   =
1
4
ℎ  =
360
× 2
   =
360
× 2 +2
   =
360
−
1
2
× 
   =
360
× 2 + ℎ