Use the Start Angle and Sweep Angle properties to change an ellipse or circle into an arc.
Ellipses and circles have a Sweep Angle of 360°. Sweep Angle values less than 360° will create an arc.
The Start Angle value determines the start point of the arc: using a clock face analogy, 0° is at 3 o'clock and increasing values move the start point in a clockwise direction.
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Figure 1  | 
		Figure 2  | 
		Figure 3  | 
	
In Figure 1 the Start Angle is 0° and the Sweep Angle is 180°.
In Figure 2 the Start Angle is 90° and the Sweep Angle is 180°.
In Figure 3 the Start Angle is 225° and the Sweep Angle is 90°.