<span>The mantle is more dense, so it can not B.
Not even A , because the crust sure does contain naturally occurring radioactive material. Heat is also not efficiently transferred to the surface--most ground is cool,
so correct option is none is above that is D
hope it helps</span>
Answer: Low oxygen content.
Explanation:
There are many dangers to the survival of fish in shallow water that depend on the properties of water.
1. The oxygen content drops during the winter and also in hot weather. Fish cannot survive without enough oxygen in the water.
2. High evaporation rates can drain the pond.
3. Fortunately, water has a high thermal mass, so overheating the water to the boiling point is not an issue.
Of the three reasons given, lack of oxygen is the most critical.
Answer:
Explanation:
It's a normal part of nature, and one of many ecological factors that help keep the hundreds of thousands of living plants. It also keeps animals in balance with one another.
Answer:
conservation of natural resources
Explanation:
You're trying to save resources, all the other options cause harm