Which of these different ecological systems do we understand the least because of its size and complexity

Brainliest ! which would require more force to move or slow down between a bowling ball and a soccer ball? explain why?

Which coal field location is related to coal fields in the eastern united states and supports the theory of continental drift? eastern india southern africa western australia northern south america

Which is an example of a vestigial structure? a. tail of a monkey b. fin of a fish c. flower of a plant d. tailbone of a human