Adepression in the ground due to a cave collapse or acidic water dissolution of limestone is called a:

a. cave.
b. stalactite.
c. sinkhole.
d. stalagmite.

What tests were able to determine when continental crust was formed?

According to the map above, all of the following areas have a high population density except

How have the russians responded to pollution and environmental challenges? a. russians largely ignore pollution and environmental damage. c. many russians have protested efforts to end pollution because it would mean people lost their jobs. b. russians have begun to focus on better resource management and protecting the environment. d. none of the above.