because it repeats every 4 numbers, so you just can change this pattern into normal, like 1 2 3 4 ... and just count, or you can just divide every number given in the choices by four
The angles that are vertically adjacent to the transversal.. when it cuts two parellel lines are always supplementary.. that is they make 180 degree.. hence, in the given pair 3 and 5 are supplementary..
