Problem: OPTIONS:
- Physical weathering
- an external framework
- Physical changes
- adding sand
- adding mud
- heating liquids
- adding water
- A solid geometric shape
Q: Fact 1: Freezing causes a solid to form. Fact 2: Freezing is a physical change. Given the two facts above, what causes solids to form?
Answer: Physical changes

Problem:OPTIONS:
- a flashlight
- electrically
- animals
- a firecracker
- power stations
- sensory neurons
- x-ray
- electrical light

Fact 1: Afirecracker converts chemical energy into sound. Fact 2: Energy is generated by sound waves. Given the two facts above, what can convert chemical energy into audible waves?
****
A: a firecracker

Fact 1: Killing microorganisms in food can be used to extend the shelf life of that food. Fact 2: Irradiation kills microorganisms that spoil food. Given the two facts above, what can be used to extend the shelf life of food?
OPTIONS:
- Cooking
- Enzymes
- rays or beams
- irradiation
- leaving food at room temperature
- Dehydration
- eating food
- grinding food
irradiation

Fact 1: Cells secrete acids and bases to maintain the proper pH for enzymes to work. Fact 2: An enzyme is a biological catalyst . Given the two facts above, catalysts require proper what to work?
OPTIONS:
- DNA
- pH
- pan
- RNA
- elevation
- time of day
- gas
- humidity

Answer: pH

Question: Fact 1: Fertilization occurs when a sperm and an egg fuse. Fact 2: After fertilization, the egg becomes diploid and is called a zygote. Given the two facts above, what forms a zygote?
OPTIONS:
- Most plants
- a sperm and an egg
- remains of prehistoric life
- bacteria
- and egg and an egg
- Leptospirosis
- a sperm and a sperm
- Plant reproduction
Answer: a sperm and an egg

input: OPTIONS:
- Warm air
- Sunlight
- heat
- stream
- rain
- Wind
- Time
- rivers Now, answer this question: Fact 1: Wind causes erosion. Fact 2: Erosion is the physical removal of rock particles. Given the two facts above, what causes the removal of rock particles?
A:
output:
Wind