Before rock can become soil, it must undergo certain processes. One process in the formation of soil involves plants. How can plants chemically change rocks into soil? OPTIONS:
- They weather rocks with acid.
- They strip the rocks of minerals.
- They break rocks into small pieces.
- They increase the density of the rocks.
A: They weather rocks with acid.

The students in an engineering class built a robot that stacks wooden blocks. A built-in computer controls the movement of the robot. The computer in the robot performs a function most similar to which part of the human body? OPTIONS:
- lungs
- heart
- brain
- arms
A: brain

In order for sediments to become rock, the sediments are generally OPTIONS:
- mixed with organic material.
- returned to their origins.
- compacted.
- liquefied.
A: compacted.

Turning off the light when leaving a room is an example of OPTIONS:
- conserving energy.
- wasting energy.
- using potential energy.
- using chemical energy.
A:
conserving energy.