Star - not dying
White-dwarf, dying
Red-Giant, near the end but will collapse or explode in a while
Stable star - haven't heard that term, but doesn't sound like it
Galaxy - a collection of stars
An average giant galaxy contains a trillion or more stars.
B.) A giant elliptical galaxy
The largest known galaxy is elliptical
A giant elliptical galaxy at the center of a dense cluster
It's not "galaxy stars", but galaxies, that have the black holes at their center.All, or most, galaxies have a giant black hole at their center.
At the centre of our Galaxy, the Milky Way
Yes, incuding a giant one at the center.
In the center of every galaxy there is a giant black hole.
The Milky Way is a Galaxy, not a planet
It looks like a giant oval.
You die of aids
at least 1 trillion or more.