When an ecosystem changes, the results are . a. all positive
b. all negative
c. neither positive nor negative
d. mixed between positive and negative

Which environment would most likely not contain fossils? a a thick deposit of cracked, dried mud b sediment deposited in a sandy river bed c intrusive rock formed from cooled magma d layers of sand accumulated for a century

Uncle tom's cabin started out as a series of articles printed in the national era, a newspaper.

Explain how the movement of tectonic plates causes the development of different landforms and naturak disasters