Fact 1: Nuclear reactions in stars causes stars to produce light. Fact 2: Nuclear reactions convert mass to energy. Given the two facts above, what causes stars to produce light?

OPTIONS:
- by making heat
- Generating heat
- converting mass to energy
- photosyntehsis
- photosynthetic pigments?
- Evaporation of water
- heat production
- hydrogen and oxygen

Answer: converting mass to energy

Fact 1: Mollusks have a circulatory system with one or two hearts that pump blood. Fact 2: Interestingly, a squid is also a mollusk. Given the two facts above, what has a circulatory system with one or two hearts that pump blood?

OPTIONS:
- squids
- fur seals
- the Sun
- goats
- the ocean
- rocks
- sharks
- a fish

Answer: squids

Fact 1: Coal is used for generating heat by burning. Fact 2: Coal and lignite are the lithified remains of plants. Given the two facts above, what are the lithified remains of plants used for?

OPTIONS:
- heat production
- generating heat by burning
- harvesting crops
- damming rivers
- food and shelter
- heat is produced
- A transportation fuel
- planting seeds

Answer: generating heat by burning

Fact 1: If soil is permeable then water easily flows through that soil. Fact 2: If a soil has high permeability, water flows through the soil more freely and may cause chemicals to leach. Given the two facts above, what may cause chemicals to leach in soil?

OPTIONS:
- soil is permeable
- Pesticides
- soil is hard
- soil is dense
- soil is eroded
- Organic compounds
- fossil fuels
- harmful substances

Answer:
soil is permeable