How did astronomers group stars? (3ways)

This large tectonic plate is bounded on three sides by whats know as the ring of fire. what is the name of this tectonic plate? a) pacific plate b) eurasian plate c) north american plate d) indo- australian plate plz it's science but there's no option for science so i picked chemistry

The formation of a solid, also known as a is an indication of a chemical change. precipitate particulate particle powder

Apush or pull that moves or changes and object when to objects touch