@TheCleanCarClub ABC is the correct order. A does not cross any lanes. So A goes first. B and C both cross lanes. The cars are driving on the left hand side of the road. So they must give way to their right. C must give way to B. So B goes next and then C goes last. So the order is ABC.
@GeometryPuzzles An isosceles triangle has two equal angles. The unlabelled angle is also 1. So the angle labelled with a question mark is 180 - 1 - 1 = 178.