Fact 1: Irradiating food can be used to kill existing microorganisms in the food. Fact 2: Irradiation causes chemical changes. Given the two facts above, what can be used to kill existing microorganisms in food?
OPTIONS:
- chemical changes
- Dehydration
- deoxyribonucleic acid
- bacteria
- an electron microscope
- hydration
- electromagnetic energy
- single-celled organisms

Answer: chemical changes

Fact 1: Powering an electrical device with a battery requires a path for electricity to flow through a closed circuit. Fact 2: Electric cars have big batteries instead of engines. Given the two facts above, an electric car requires what to operate?
OPTIONS:
- radiation shielding
- hydrogen and oxygen
- electromagnetic energy
- gasoline
- direct energy
- heat energy
- a closed circuit
- oxygen

Answer: a closed circuit

Fact 1: If soil is permeable then water easily flows through that soil. Fact 2: Permeability is affected by many soil characteristics. Given the two facts above, what is the rate of water flow of soil?
OPTIONS:
- salinity
- variable
- heat energy
- reduce
- streams.
- streams
- down
- evaporation

Answer:
variable