Answer:
Hydrogen emits and absorbs light at specific wavelengths, therefore if you're looking at a distant cloud that produces a certain spectrum
Explanation:
The conditions which are most favorable for the formation of radiation fog are warm, moist air over low flat land areas,on clear, calm nights.
Radiation fog is most prevalent during the winter and fall; it usually forms overnight as the air closest air to the ground cool down. When the cooling makes the air to reach saturation point, radiation fog will formed.
Answer:
Archaeologist.
Explanation:
I believe this is the only on of the four that deals with post-mortem study of bones, other than a forensic odontologist, who studies teeth and bitemarks, but not bones in general.