Which is a closed system. a tree, a human ,a clock , or a car

Indicate whether the following statements about the biases in the fossil record are true or false. a) inland species are more likely to be preserved than marine species b) organisms with hard body parts are more likely to be preserved than are those composed soft tissues. c) species that existed over a larger area are more likely to be preserved than species existing over a smaller area. d) organisms that lived very long ago are more likely to be found as fossils than organisms that lived relatively recently e) the fossils of larger organisms are more likely to be found than the fossils of smaller organisms

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?

About how much of the cell mass is watet