Answer:
Oxygen became available from cyanobacteria
Explanation:
Answer:
Oxygen in the atmosphere is a molecule because it contains molecular bonds. It is an element because it is made from atoms of only one element - oxygen.
Explanation:
Ex: Draw the United States, then draw a transform plate boundary starting in the middle of California down into the ocean.
Answer: One kind of evidence that supports Wegener's hypothesis is that: fossils of the same organism have been found on different continents Based on this finding, we can draw a conclusion that million years ago, all the lands on the face of the earth were not separated by sea so the animals could migrate from one continent to
