In the diagram provided, line l is parallel to line m. Select which of the following statements could be used to prove that the interior angles of a triangle have a sum of 180°. You may choose more than one correct answer.
m 4 + m 5 + m 6 = 180.
1 and 4 are alternate interior angles.
m 5 = m 3 + m 2
. m 5 + m 1 = 180.