2)
(a segment bisector divides a segment into two congruent segments)
3)
(a segment bisector divides a segment into two congruent segments)
4)
(vertical angles are congruent)
5)
(SAS)
6)
(CPCTC)
7)
(converse of alternate interior angles theorem)
8)
(segments collinear with parallel segments are parallel)
9)
(alternate interior angles theorem)
10)
(congruent angles added to congruent angles form congruent angles)
11)
is a parallelogram (a quadrilateral with two pairs of opposite congruent angles in a parallelogram)