(a)
The corresponding angle are those which lies on same side of transversal line but one lies inside the a parallel and other one lies outside the second paralle line.
So angle 2 angle 6 are pair of corresponding angles.
Answer: 6
(b)
The same side interior angles are those angle that lies on side of transversal line and inside the parallel lines.
So angle 3 and angle 6 are pair of same side interior angles.
Answer: 3
(c)
Alternate interior angles are those that lies on opposites sides of tranversal line and inside both the parallel lines.
Angle 6 and angle 4 are alternate interior angles.
Answer: 4