Geometry Problem 981.
Triangle, Concurrent Cevians, Midpoints, Area, Hexagon.

Geometry Problem 982.
Triangle, Excenters, Excentral Triangle, Circumcenter, Area, Hexagon.

Geometry Problem 983.
Regular Hexagon, A point and six triangles, Areas.

Geometry Problem 984.
Triangle, Circumcircle, Altitudes, Midpoint, Collinear Points.

Geometry Problem 985.
Circle, Radius, Perpendicular, Concentric Circles, Congruence, Triangle.

Geometric Art of Problem 985.

Geometry Problem 986.
Triangle, Median, Midpoint, Equal Angles, 45 Degrees.

Geometry Problem 987.
Triangle, Circumcircle, Incenter, Chord, Parallel, Circle, Tangent. GeoGebra, HTML5 Animation for Tablets (iPad, Nexus).

Geometry Problem 988.
Right Triangle, Cevians, Angles, 30 Degrees, Triple Angle.

Geometry Problem 989.
Arbelos, Semicircles, Diameter, Perpendicular, 90 Degree, Common External Tangent, Rectangle, Midpoint of Arc.

Geometry Problem 990.
Triangle, Incircle, Median, Cevian, Central Angle, Congruence, Circle, Secant, Midpoint, Parallel.