The leaf because it is the major structure of photosynthesis in a plant.
I believe the answer would be D. If a plant were to have poisonous parts it could me the possibility that a child could become seriously ill.
What was the investigation? But from my best guess I'm assuming it's the second option. This may be incorrect.
I believe Enthalpy is the scientific term for the changes. The specific changes each item listed undergoes is hard to say correctly without knowing the options. Could you list the answers to choose from so I can get a better understanding of what they want in the answer?