How can brincle(natural phenomena) happen

"water seeps into rock cracks and dissolved minerals there. the solution travels through cracks in the. eventually concentrating into large crystals." which process is that

Which of the following is not a challenge to instituting sound global environmental policies? a. most changes are inexpensive and easy to implement. b. elected leaders who support unpopular environmental issues often are not re-elected. c. economic considerations outweigh environmental ones in many societies. d. there is no way to enforce international environmental agreements.

What could the united states of america do to improve their status? name at least 3(ap human geography)