Hey buddy,
I believe the answer should be
→ <span>By mass, </span>one half<span> of the atmospheres volume </span>lies below<span> an </span>altitude of<span> 5.6 kilometers</span>←
It is B, <span>In fact, water will sink as it cools until a certain point. If I recall correctly this is around 39 F. As the temp gets lower than that water actually begins to expand and becomes less dense. This is why ice floats, which we should all be thankful for. If ice didn't float than all water on earth would likely freeze solid and life would have probably never evolved past small single celled things.</span>
