You'd expect the DO to be lower in the morning. Photosynthesis doesn't occur at night and the DO would drop overnight due cell respiration.
it would move to where there is a higher concentration of sugar molecules
The concentration of carbon dioxide over an industrial site might be higher, because of the emissions, however, carbon dioxide mixes well with other gases, so it will spread out all over the world.
From areas of higher concentration (of water) to lower concentration (of water) - ie it fills the space. That would mean that it would flow from a solution whose concentration of solute is higher to one where the solute concentration is lower.
Because the surrounding freshwater concentration is higher than the salt concentration inside and so all the water from the vacuoles has left because of osomosis. while the marine amoeba has the surrounding salt concentration equal to the concentration inside the vacuole.
You would expect a corrosive symbol, or an irritant symbol, depending on the concentration.
Physically I would expect to find the same boiling and melting points, and the same density. Chemically, I would expect the same reactivity with other substances.
It is possible to tell the difference between two samples of water, yes. If you have reference samples, you could even tell which of them was from where. Without reference samples, you'd have to make some guesses about what you would expect New York water to be like vs. what you would expect Idaho water to be like (I'd expect NY water to be softer, but I'm not a geologist and could easily be wrong about that.)
higher
Osmosis. A solution with a low concentration of solutes would have a higher concentration of water than a solution with a high concentration of solutes. So in this case, water is moving from a higher concentration of water to a lower concentration of water, which is osmosis.
The concentration; to prepare a solution the compound must have a solubility.
faster in higher altitiudes
Higher