Which event helped get the voting age lowered to 18?

The military drafts around the vietnam war also helped.

Dis the awnser because they are going from high to low

Which of the following is an example of an opposing signal? no examplthates given.   i would say, that traffic lights in a city at major intersections direct the flow of traffic in opposite directions so would be an example.also, stop signs on either side of the same street would be an example. at a train crossing, the light for allowing car traffic in opposite directions or not would be another example.