The answer is B.
Animals do cellular respiration which requires the intake of oxygen and the output of carbon dioxide. In order for plants to do photosynthesis, they need carbon dioxide to be able to make oxygen for animals to breathe.
There are three major types of blood vessels: the arteries, which carry the blood away from the heart; thecapillaries, which enable the actual exchange of water and chemicals between the blood and the tissues; and the veins, which carry blood from the capillaries back toward the heart.
Is that a test your taking?
The chemical formula for water is H2O which means that every molecule of water has 2 atoms of hydrogen (H) and one atom of oxygen (O). Here comes the key part. From the Periodic Table of Elements, one sees that one molecule of oxygen atoms weigh 16 grams.
I apologize if this is not what you meant. If you have further questions just tell me.
Answer:
true
Explanation:
the condenser lens is the size of the electron beam and the main objective lens is to focus the beam on the sample
so that scanning electron microscope have two projector lens
sorry if its not correct
