What are his observations? We can’t answer this without knowing his observations if those are the conclusions. Please provide the rest of the information and I can answer.
Because sugar in fruits is good for you but artificial sugar isn’t healthy for you
The independent variable is the one that can be changed
I think the correct answer would be water temperature because on the table, the water temperature is increasing by 10 each time so it is changing.
hope I'm right and hope I helped :)