Working with circle and ellipse - 1

1.) Use the circle-tool to draw a circle with center A through F 2.) Use the circle-tool to draw a circle with center A through C and B Check it with "Check 1" 3.) Use the ellipse-tool to draw an ellipse with center C and A through B 4.) Use the ellipse-tool to draw an ellipse with center D and E through B Check it with "Check 2" What is the difference between a circle and an ellipse?