We breath oxygen because it is needed to burn fuel [ sugars and fatty acids] in our cells to produce energy. Oxygen is also brought into the lungs via breathing; where it is transported by red blood cells to the entire body to be used to produce energy. The food we eat gives us protein, sugars, vitamins etc. for energy
Grazing animals such as deer are primary consumers.
C. When you take a step, the ground pushes back on your foot with the same amount of force. If it pushed back with less, your foot would go through the floor; if it pushed back with more, it would actually push your foot off the ground. But they're in opposite directions; your foot pushes down, while the ground pushes up.
Hope this helps!
