A. The oxygen means it's a respiratory, and the hairs act to ensure no foreign contaminants make you sick.
The parameter pH is a measure of the substance's acidity or basicity. It is quantitatively equal to the negative logarithm of the concentration of H+ ions. So, the lower the pH, the more acidic the substance, Otherwise, the higher the pH the more basic the substance. The pH range runs from 1 to 14, with 7 being neutral.
So, if we are asked to distinguish which of those have the lowest pH, we have to know the moles of H+ ions. Since all of them have a concentration of 0.1 M, concentration is not a factor. Thus, we just have to identify the strongest acid among the list. That is easy to answer because you only have to remember 7 strong acid occurring in nature: HCl, H₂SO₄, HNO₃, HClO₄, HClO₃, HBr, and HI. Since only HNO₃ is included in the list among the choices, the answer would be letter D.
Through hypothesis and experiments
I would say the head and heart because if you swim deep in the ocean you will feel pressure in your heart and head because the muscles in your body are closing in on them
hope i helped
<u>Answer:</u> The correct option is C) decomposition
<u>Explanation:</u>
Single displacement reaction is defined as the reaction where a more reactive element displaces a less reactive element from its salt solution.

Element B is more reactive than element A
Double displacement reaction is defined as the reaction where an exchange of ions takes place in a solution

Decomposition reaction is defined as the reaction where a single large chemical species breaks down into two or more smaller chemical species.

Synthesis reaction is defined as the reaction where two or more smaller chemical species combine together in their elemental state to form a single large chemical species.

For the given chemical reaction:

Here, water is breaking down into two smaller species of oxygen and hydrogen gas. Thus, it is a decomposition reaction.
Hence, the correct option is C) decomposition