<span>The magnetic field of the Earth serves a useful purpose in deflecting Solar radiation. Without the magnetic field there is much more charged-particle radiation striking the surface. The auroras would occur everywhere instead of at the magnetic poles. Compass needles wouldn't work, and then they would flip direction.. The magnetic field IS DECREASING and could go to zero and reverse sometime in the next few tens-of-thousands of years.</span>
Hi there! Air and sunlight can definitely be reused. Those are abundant and renewable resources. Therefore, A and D are eliminated. There is a limited amount of water, however, it's impossible to run out of it to the point that there's no more on Earth. C is out. The only answer choice that makes sense is coal, because it's a nonrenewable resource, and it takes millions of years to make more of. It's a fossil fuel, so once we use them up, we can't get anymore during our lives. The answer is B: coal.
The answer could possibly be D.) The product have more potential than the activated complex OR C.) Forming the activated complex requires energy .