Answer:
A: angle A is 90°, angle B is 90°, angle C is 90°, and angle D is 90°
B: angle A is 80°, angle B is 80°, angle C is 100°, and angle C is 100°
D: angle A is 60°, angle B is 50°, angle C is 120°, and angle D is 130°
Step-by-step explanation:
The sum of opposite angles of a cyclic quadrilateral is 180°
It must satisfy the following:
A+C=180° and B+D=180°
Only choice A and B and D satisfy.