Yep, your answers are correct - For a task like this where you are given 3 salt concentrations and are not given the cells solute concentration you can normally assume that the middle value will be isotonic. I've edited your answers a bit to give you an idea of how you should approach them - the way you wrote these are correct but they could be more specific and concise - it's something you will get better at as the year goes on.
(A) = Distilled water has a lower solute concentration (0M). outside the cell, as compared to the whereas cell fluid which has a higher solute concentration. Thus Meaning, this rhubarb cell was placed in a hypotonic solution. As a result, the rhubarb cells take up water molecules via osmosis and so the cells start to swell (cells become turgid), as osmosis is occurring. However, the cell wall of rhubarb cells prevent it from bursting. Pressure inside the cell also increases until the pressure inside is equal to the pressure outside
(B) = The 0.17M salt solution A dilute salt solution has equal solute concentrations to the solute concentration inside the cell, they are isotonic. on both the inside and outside of the cell. Therefore, there is no net osmotic movement of water.
(C) = The 2M salt solution is hypertonic to the solute concentration inside of the cell. A strong salt solution has a higher solute concentration outside the cell then inside. Thus, this rhubarb cell is placed in a hypertonic solution. As a result, the osmotic pressure will cause the water to move out of the cell through the cell membrane. Rhubarb cell becomes flaccid and plasmolysis occurs as the cell shrinks and moves away from the cell wall.
I am being super nitpicky here – Unless you’re teacher is super harsh, I expect that you would get full marks for your answers. The most important things that I have changed here is that you must be specific with your answers – especially for the end of year exam, if you are given specific values but don’t use them, you will lose marks. Most of the other things I changed are just for the sake making your answer more precise – not particularly important for homework, but in a sac/exam it will save you a lot of time. You should also avoid shortening words like conc. (meaning concentration) unless it is said like that in the question. Some words can be shortened (like Endoplasmic Reticulum to ER, because that is common in biology, but I would avoid shortening non bio-specific words.
I'm being super harsh, so don't worry too much but saying:
A strong salt solution has a higher solute concentration outside the cell then inside.
Doesn't make it particularly clear, for all I know both sides of the semi-permeable membrane are salt solutions. It implies that the strong salt solution is on both sides of the cell, which is not correct.