[size=150]1. [b]Angles [/b]at the [b]circumference[/b] subtended by [b]arcs of the same length[/b] are [b]equal[/b].[br]2. The [b]size of an angle[/b] at the [b]circumference[/b] subtended by an arc is [b]proportional[/b] to the [b]arc length[/b].[/size][br][br]The arc length of BG is equal to the arc length of ED. You may adjust the point F and C to determine the value of them. Is it still the same angle?

The arc length of ED is double the arc length of ED. You may adjust the point F and C to determine the value of them. Is the angle value of F still double of the angle value of C?