Question

what is true regarding two adjacent arcs created by two intersecting diameters?○ they always have equal measures.○ the difference of their measures is 90°.○ the sum of their measures is 180°.○ their measures cannot be equal.

Explanation:

Two intersecting diameters form a straight angle (180°) at the circle's center. Adjacent arcs created by these diameters correspond to the angles that make up this straight angle, so their measures must add up to 180°. The other options are incorrect: adjacent arcs only have equal measures if the diameters are perpendicular (not always), their difference is not fixed at 90°, and they can be equal.

Answer:

The sum of their measures is 180°.