I believe the answer is Density have a very nice day
Answer:
Nitrate deficiency
Explanation:
Plants absorb nitrates in water through their roots. Nitrates are present in high levels in plant fertilisers. Without nitrates, the amount of chlorophyll in leaves reduces. This reduces the plant's ability to photosynthesise and grow properly, which reduces the farmers' crop yield .
Answer: they allow air to enter lungs and also permits air into the body
Explanation: