Answer:
The electronic configuration of the element with Atomic number 19 is 2,8,8,1. The element is potassium. It is an alkali metal with one valence electron.
B.
The cynobacteria were already there without the oxygen, so that rules out A, and a lot of prokaryotes were anaerobic, so that rules out C. Finally, Photosynthesis does not require oxygen. Instead, Oxygen is a waste product of it. Therefore, it cannot be D. So, we are only left with B
Hoped this helped :D
Answer:
Potential energy
Explanation:
The thrown baseball is converting from kinetic energy into potential energy. When it finally stops at a particular height, it attains its maximum potential energy at the position or point.
- Potential energy is the energy at rest of body.
- Kinetic energy is the energy due to the motion of body.
The more a body speeds, the higher its kinetic energy attained.
As a body comes to rest, at a height, it attains potential energy.
The body during flight decreases in kinetic energy but increases its potential energy due to gravity pulling it to rest.
Using the VSEPR theory, the electron bond pairs and lone pairs on the center atom will help us predict the shape of a molecule. The shape of a molecule is determined by the location of the nuclei and its electrons. The electrons and the nuclei settle into positions that minimize repulsion and maximize attraction.
