Which pair of triangles must be similar? (hint: try drawing the triangles in the space below) a. Triangles 1 and 2 each have a 35 angle. b. Triangles 3 and 4 are both isosceles. They each have a 40 angle. C. Triangle 5 has a 30" angle and a 90 angle, Triangle 6 has a 30 angle and a 70" angle. D. Triangle 7 has 50" angle and a 25" angle Triangle 8 has a 50 angle and a 105 angle.