B. thick atmosphere
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Answer:
many alveoli are present in the lungs with a shape that further increases surface area. Thin walls - alveolar walls are one cell thick providing gases with a short diffusion distance. Moist walls - gases dissolve in the moisture helping them to pass across the gas exchange surface.
Explanation:
Answer: Food groups were coded by stripes in widths corresponding to the recommended servings from each group. All the stripes tapered toward the top of the pyramid to remind people that each food group includes both healthy and unhealthy choices, such as foods with added sugar or “solid” fat.
Explanation:
