12.2 - 12.3 Inscribed Angles

Drag points C and D to change the arc. Drag point E to change the inscribed angle (but keep point E outside points C and D).
As you change the arc or the inscribed angle, how is the measure of the inscribed angle related to the central angle for the arc? Keep in mind that rounding is taking place, so focus on values of the central angle with the last decimal even.