The us has way more things to help fight such as medicines
Incoming solar radiation is almost double at the equator then at the poles, causing the water closer to the equator to be warmer. The heat difference also causes the oceans to swirl so the water that is around the equator will eventually end up at the poles and keep circulating around.
The answer to your question is a
A common crescent-shaped dune with horns pointed downwind is called a barchan dune.
A barchan or barkhan dune is a crescent-shaped dune. Barchan ("BAR-kahn") dunes form in areas with only one wind direction, and little or no vegetation. If conditions were "perfect"—the landscape was flat, winds blew from only one direction, vegetation could not grow, and sand was available but limited —barchan dunes would dominate a sandscape. One of the commonest types of dunes, it occurs in sandy deserts all over the world. Barchans are mostly formed by the wind from one direction and appear convex. They are arc-shaped, significantly asymmetrical in cross-section, with a gradual slope towards the wind sand ridge, and made out of well-sorted sand.
To learn more about barchan dune here
brainly.com/question/2515927
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Because sunlight does not reach all the way to the bottom of the lake :)
