Astronomers estimate that a galaxy .100 stars b.1 star .c, millions or billions of stars or d.100,000 stars ?

halogen, any of the six nonmetallic elements that constitute group 17 (group viia) of the periodic table. the halogen elements are fluorine (f), chlorine (cl), bromine (br), iodine (i), astatine (at), and tennessine (ts).

answer; ///i believe the correct answer is (aids) acquired immune deficiency syndrome;