*Question*: How do scientists know that some mountains were once at the bottom of an ocean? OPTIONS:
- Freshwater rivers flow to the ocean.
- Saltwater fish are found in some mountain streams.
- Dinosaur bones have been discovered in the mountains.
- Marine fossils have been found on the peaks of some mountains.
*Answer*: Marine fossils have been found on the peaks of some mountains.

*Question*: Which of these resources will most likely be depleted first? OPTIONS:
- Wind
- Solar energy
- Fossil fuels
- Water
*Answer*: Fossil fuels

*Question*: Signs in many stores and restaurants warn that microwaves are in use. What is the main reason for this warning? OPTIONS:
- Some people do not like food cooked in microwave ovens.
- Microwaves sometimes affect people's sense of sight.
- Microwaves sometimes cause hair or teeth to fall out.
- Some people have pacemakers that may be affected by microwaves.
*Answer*:
Some people have pacemakers that may be affected by microwaves.