CIRCLES
CHORDS
www.mathopenref.com/chord.html
CENTRAL ANGLES - colored yellow
www.mathopenref.com/circlecentral.html
INSCRIBED ANGLES - colored white
www.mathopenref.com/circleinscribed.html
PERPENDICULAR BISECTOR OF A CHORD and the CENTER
http://www.mathopenref.com/constcirclecenter.html
TANGENTS - line AP and line BP
www.mathopenref.com/tangent.html
ANGLES INSCRIBED IN A SEMICIRCLE
www.mathopenref.com/semiinscribed.html
SECTORS - slices of PIE - colored yellow above
www.brightstorm.com/d/math/s/geometry/u/area/t/area-of-a-sector
Circle SEGMENT - colored green above
www.brightstorm.com/d/math/s/geometry/u/area/t/area-of-a-segment
CYCLIC Quadrilateral
en.wikipedia.org/wiki/Cyclic_quadrilateral
TANGENTS AND CIRCLES
www.regentsprep.org/regents/math/geometry/GP14/TanCircles.htm
http://www.brightstorm.com/math/geometry/circles/arc-length/