standard_description: Solve real-world and mathematical problems involving area, volume and surface area of two- and three-dimensional objects composed of triangles, quadrilaterals, polygons, cubes, and right prisms.
problem_activity: Circle
$$A$$
is shown below.
[IMG]
Draw two diameters of the circle.
Identify the shape defined by the end points of the two diameters.
Explain why this shape is always the result.


aligns: no