Circular Ring Sector.
If they're in the same circle or in circles of equal radii (radiuses), then yes.
Adjacent Arcs
Circles have infinitely many arcs, not just 3.
No
Diameter
The answer is false
If they're in the same circle or in circles of equal radii (radiuses), then yes.
Yes, there can be congruent arcs on a circle. Arcs which subtend the same angle at the center are considered as congruent.
Divide 360 by 14, then draw two radii in the circle with this number of degrees between them. Then use a compass to mark off 14 equal arcs around the perimeter. Join the points to the centre.
Congruent Arcs
Circles have infinitely many arcs, not just 3.
Adjacent Arcs
Half of the circle is an arc
No
Because they are parts of the circumference of a circle
Diameter
In the same circle, or in congruent circles, two minor arcs are congruent if and only if their corresponding chords are congruent.