No one knows the answer to that because astronomers haven't been able to explore any other galaxies besides the Milky Way.
ALL of them, except the Milky Way and the Andromeda galaxies.
no.
they all are in space?
The Milky Way Galaxy and about 17 other galaxies within 3 million light-years are collectively known as the Local Group. This group includes galaxies such as Andromeda (M31), Triangulum (M33), and the Milky Way.
All galaxies have black holes, even the Milky Way.
Neither. Among those galaxies observed so far, there are many larger than the Milky Way,and many others that are smaller. Enough have been observed to estimate that there arebillions more, of all sizes. There's nothing unusual or unique about the Milky Way, exceptthat it contains us.
Main sequence stars are found in all galaxies.
All of them. The Solar System is part of the Milky Way Galaxy, one of several billion galaxies in the Universe.
Not all galaxies have a black hole at their center. Some galaxies, like our own Milky Way, do have a supermassive black hole at their center, while others do not.
Not all galaxies have black holes in their centers, but many large galaxies, including our own Milky Way, are believed to have supermassive black holes at their centers.
The stars in the Milky Way move in the opposite direction of the sun.
The largest Galaxy ever discovered was IC1101, an Elliptical Galaxy, but the most common large ones are Spirals such as the biggest Galaxies in the Local Group, Andromeda, Milky Way, and Triangulum; all Spirals.