What is the diffrence between a star and a planet

A star is a celestial body that produces its own light due to a reaction at its core. There are millions of stars. On the other hand, a planet is a celestial body that has a fixed course, otherwise known as an orbit. The orbit is the pathway that allows the planet to move around a star.

The answer is oh i forgot 

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.