Answer:
Placer mining can be less damaging to the environment than surface mines, as the sediment is returned to the water after the minerals have been extracted.
Explanation:
There was no life on Earth for the first billion years because the atmosphere was not suitable for life. Earth's first atmosphere had lots of water vapor but had almost no oxygen. Later, frequent volcanic eruptions put several different gases into the air.
I think C would be correct
Answer:
True
Explanation:
Yes, scientists have observed many mysteries of plants.
A heterotroph is an organism that relies on complex organic substances for nutrition. <span>A </span>heterotroph<span> is an animal that can't make its own food supply, so they have to eat other things, like plants or other animals, to survive. Hope this answers the question.</span>
