I need the answer and the work (it’s geometry)

Which is a true statement about an exterior angle of a triangle a. it is formed by two segments that are not sides of the triangle, b. it forms a linear pair with one of the interior angles of the triangle, c. it is complementary to one of the interior angles of the triangle. d. it is formed by two segments that are sides of the triangle.

How to simply and write the answer n a whole number

Which graph has figures that can undergo a similarity transformation to justify that they are similar? (obviously not the third one)