B. The unknown solution had the lower concentration.
Explanation:
Osmosis is a phenomenon in which the molecules of the solvent has a tendency to move through a membrane which is semipermeable from lower concentrated side to the higher concentration side, so that the concentrations on both sides of the membrane must be equal.
So the unknown solution may have lesser concentration than the isotonic solution so that molecules of that solution move from less concentrated side to the more concentrated side, so its level drops.
Are you referring to DNA?
The solution is an alkali.
Usually with the pH value range of 14, substances with pH 7 can be called neutral. Meanwhile substances lower than pH 7 are acids, the lower the pH is, the more acidic it is. Such as cola, it has a pH 2, which is very acidic.
In opposite, the substances with pH over 7 are called alkalis. Again, the larger the pH value is, the more alkaline it is. So pH 13 is a strong alkaline therefore it it corrosive and can clean the toilet well.
Answer:
Because water conducts electricity, so if an electrical current were to meet the water while you're in there taking a bath, you would essentially be surrounded by a huge conductor.