9cm is equal to what in mm

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.

Complete the equation of the line through (−10,3) and (−8,−8). use exact numbers.

Terri makes a quilt using three sizes of fabric squares the side lenght of each fabric square is the square root of the area