Smog. Im pretty sure smog is the only unhealthful air pollution on this list.
<span>from low concentration to high concentration</span>
Krypton's atomic number is 36. This tells us that an atom of krypton has 36 protons in its nucleus<span>.</span>
A star’s life expectancy depends on its mass. Generally, the more massive the star, the faster it burns up its fuel supply, and the shorter its life. The most massive stars can burn out and explode in a supernova after only a few million years of fusion. A star with a mass like the Sun, on the other hand, can continue fusing hydrogen for about 10 billion years. And if the star is very small, with a mass only a tenth that of the Sun, it can keep fusing hydrogen for up to a trillion years, longer than the current age of the universe.
Answer:
I believe the answer is A
Explanation:
I think it is A because the original function of the spinal cord is to complex organization of nerve cells responsible for movement and sensation. It carries signals between the brain and the rest of the body.
