I don't like this kind of answers but..
From GraphicsPath.AddArc Method (Int32, Int32, Int32, Int32, Single, Single)
width
The width of the rectangular region that defines the ellipse from which the arc is drawn.
height
The height of the rectangular region that defines the ellipse from which the arc is drawn.
startAngle
The starting angle of the arc, measured in degrees clockwise from the x-axis.
sweepAngle
The angle between startAngle and the end of the arc.