In the figure, x∥y and a is a transversal that crosses the parallel lines.

which angle pair forms alternate exterior angles?

∠2 and ∠8

∠3 and ∠5

∠2 and ∠6

∠4 and ∠6

Assuming the top left-most angle is 1 and going clockwise the angles are 2, 3, 4 and the lower portion's angles are 5, 6, 7, 8 in a clockwise manner,
The alternate angles will be 
∠2 and ∠6

Six people to the minimal staar