an odd number interstate with a single or double digit number indicates a route that:
runs north and south
A solid yellow centerline on your side of the road means:
you may not pass
solid white lines are used…
to mark the right edge, of the highways, and between lines to indicate areas were lane changes are discouraged, or unlawful.
traffic control devices communicate meaning using…
Color shape, and wording
Railroad advanced warning signs are…
yellow and round