The main purpose is communication. like when you stub your toe , your nervous system communicates to your brain to react and have pain
There are different star systems. Binary star systems consist of two stars. Multiple star systems consist of two or more stars. The meaning of star system is "A small number of stars."
I think it's either A) a group of hundreds of stars, or B) a group of two or more stars. I would assume it's B), but i could be wrong.
Hope this helps!
Answer:
it provides energy to the body.
Mass transit can help reduce air pollution in urban cities because there are fewer cars on the roads, creating less pollution.