Help me please

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.

Sketch, label, and explain the rock cycle. your sketch should contain descriptions of all eight key processes. in addition, use sentences (no sketch) to describe why a rock might not experience the entire rock cycle.

What is a boundary between geologic units called