Answer:
electromagnetic wave
Explanation:
Electromagnetic waves differ from mechanical waves in that they do not require a medium to propagate.
Oxygen is -2, Na is +1, and Mn is +7
oh its a Chlorine isn't it....
it's electronic configuration is
2,8,7
so to make it 8 in its outermost shell it should gain 1 electron...
D. Black holes
When a star dies out it explodes and causes a supernova and after a very long period of time the supernovas gasses vanish and the star can be visibly identified as a black hole!
