The structure labeled "A" open and close the sites where the gases, carbon dioxide and oxygen, are exchanged during photosynthesis. What is the structure labeled A?

What best explains the inability for life to exist in earth early atmosphere

Diego conducted an experiment to find out what kind of ball bounces the highest when dropped from a five-foot platform. he used a golf ball, a tennis ball, and a soccer ball. he dropped each ball from the balcony once. diego recorded his observations after each drop. what can diego do to best improve the reliability of his results? a) drop each ball from the platform three more times b) record his observations in more than one unit c) write at least two scientific questions after the experiment is complete d) share his results with other people who have done similar experiments you for the !

During convection, less dense fluid rises and denser fluid sinks.