a. Hydrogen
Hydrogen has a line at 410 nm.
Mercury has a line at 405 nm.
Sodium and neon have no lines near 412 nm.
Carbon dioxide
Explanation:
because when hydrogen mixes with oxygen carbon dioxide is canceled out
Number of moles = number of atoms/Avogadro's number
= (4.8x10^25)/(6.02x10^23)
=79.7 mol (3sf)
Nonmetals i believe are last groups
The universe moves with the energy left off from the big bang. This is why the universe constantly expands.
Things rotate and revolve because of gravity.
Hope this helped!