The correct answer is option B, hydrogen.
The majority of the atmospheric gases are found in the sea water solution. In supplementation to oxygen and nitrogen, the most profusely found gas in the atmosphere, that is, carbon dioxide is found in the ample concentrations in the ocean waters.
However, hydrogen is not present, and if found it is found in minute concentration. Of the gases, nitrogen is the most abundant gas found in seawater, while oxygen is the second most abundant, and carbon dioxide is the most soluble gas, and one of the various constituents, which influences the pH balance of the ocean.
I also believe the answer is A.
This is referring to meiosis, which happens just once to make reproductive cells, unlike mitosis which is just simple copying.
In mitosis, one cell splits into two, but the number of chromosomes doesn't change. The original cell makes two copies of its chromosomes and divides them up.

In <em>meiosis</em>, however, our cell doesn't bother making those two copies. It just takes what it has and divides it between two new cells.
Answer:
An action potential is part of the process that occurs during the firing of a neuron. During the action potential, part of the neural membrane opens to allow positively charged ions inside the cell and negatively charged ions out. ... This electrical impulse is carried down the nerve through a series of action potentials.
Explanation: