1: Plants do not have a digestive system like us. Why do they not need a digestive system?
2: Plants surviving around the mining regions had a lot of dust settled on its
leaves and were stunted and fruitless. Why?
3: Some plants close their stomata during the hottest part of the day, despite
the effect on photosynthesis. Suggest what benefit this might be to the
plants?

Plants do not have a digestive system because their need for nourishment is fulfilled through the process of photosynthesis and cellular respiration. They obtain their energy and and nutrients from the energy of the sun to create their supply to live.The answer in the picture givenCertain plants close their stomata during the hottest part of the day so that the amount of loss of water by the process of transpiration is reduced. It help the plant to stop excessive transpiration.

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The answer is reflection.