Describe the difference between a perfect circle and an ellipse

A circle is a closed curved shape that is flat. Instead of having all points the same distance from the center point, though, an ellipse is shaped so that when you add together the distances from two points inside the ellipse called they always add up to the same number.

20: 5

explanation:

about 20% of the world's population lives in   southwest asia, but on less than 5% of the world's   land area.