The remains of plants and animals preserved by natural causes in the Earth's crust
Seawater that has dried and formed crystals
What the climate was like and what animals lived during certain time periods.
How the Earth was formed.
Fossils can't really tell you anything since they're no longer living
All of the above
It hunted alone.
It lived in groups.
It was the only species there.
It did not produce many offspring.
Here's an interesting quiz for you.