What is part B I need more info.
True, most cells are to small to see with the naked eye
Answer:
First peak which touches the A line
Answer:
Plants and animals use oxygen to respire and return it to the air and water as carbon dioxide (CO2). CO2 is then taken up by algae and terrestrial green plants and converted into carbohydrates during the process of photosynthesis, oxygen being a by-product.
Explanation: