B:2 it is measured by the crest of the wave or as I say the top of the wave
natural selection, bc it is the process whereby organisms better adapted to their environment tend to survive and produce more offspring
All galaxies have a dense core of stars. Spiral galaxies, however, have arms that are often visible. There are two kinds of spiral galaxies: barred, where there appears to be a line running from arm to arm through the core, and <span>ordinary, where there is no bar. @Badbunnyhunny</span>
Answer: Option A) Oxygen may not have been able to accumulate in the atmosphere
Explanation:
Ozone, O3, is an allotrope of oxygen having three atoms in the molecule instead of the usual two present in molecular oxygen. Ozone is generated from oxygen, and is the only form in which oxygen can exist in the atmosphere.