Answer:
The correct answer is b. The oldest generally accepted fossils of large animals range in age from 565 to 550 million years old.
Explanation:
The oldest one of them all is the hematite tubes, that are dated about 3.77 billion to 4.2 billion years and it's from a yet unknown bacteria.
Answer:
Speed.........................................
Both. You can use it as singular or plural.
Yes. No cancer and heart disease would save millions of lives.