Parallel lines in space are coplanar. a. always b. sometimes c. never select the best answer from the choices provided

Danny draws a transversal, t, on two parallel lines ab and cd, as shown below: he makes the following table to prove that the alternate interior angles are equal: which is the missing justification? (6 points) corresponding angles formed by a transversal on parallel lines are supplementary. corresponding angles formed by a transversal on parallel lines are congruent. co-interior angles formed by a transversal on parallel lines are congruent. co-exterior angles formed by a transversal on parallel lines are congruent.

Select the best attribute for the angle pair formed by two parallel lines intersected by a transversal.

What is the missing step in this proof ?