CO observations of the galaxy reveal a. the location of dense ...

[tnt_battle]

CO observations of the galaxy reveal
 
  a. the location of dense neutral hydrogen clouds.
  b. the location of population II stars.
  c. the location of population I stars.
  d. the location of the galactic corona.
  e. the location of giant molecular clouds.

Question 2

If a star's spectrum does not contain spectral lines characteristic of a certain element, can we conclude that the star does not contain that element? Why or why not?
 
  What will be an ideal response?

[guyanai]

Answer to Question 1

e

Answer to Question 2

We cannot conclude this, because it might be that the star is too hot or too cool for the electrons in a particular element to absorb photons.

[tnt_battle]

Both answers were spot on, thank you once again

[guyanai]

Great! Please up vote