Problem:OPTIONS:
- When magma warms up
- flow of electrons
- it can be seen
- permineralization
- When magma cools
- aqueous solution
- When the air is cold
- When water rises

Fact 1: Vein deposits of gold and silver are formed by igneous intrusion. Fact 2: Magma that cools slowly deep below the surface produces coarse-grained intrusive igneous rocks. Given the two facts above, when do vein deposits of gold and silver form?
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A: When magma cools

Problem:OPTIONS:
- Plants
- expelled
- heat
- recycling
- glucose
- trees
- food
- state

Fact 1: Most ecosystems get energy from sunlight. Fact 2: Plants use sunlight to make energy. Given the two facts above, where does the energy in ecosytems come from?
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A: Plants

Problem:OPTIONS:
- humans
- They lay eggs
- Tropical
- bees
- insects
- subtropical
- perennials
- heterotrophs

Fact 1: Plant reproduction requires pollination. Fact 2: Perennial types are planted outside in spring. Given the two facts above, what reproduction requires pollination?
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A: perennials

Problem:OPTIONS:
- solutes
- NaCl
- juice
- grass
- liquid
- seawater
- blood
- water

Fact 1: Thirst is used to make an animal realize that it needs to replenish its bodily water by the body. Fact 2: Today's animal is the cow. Given the two facts above, thirst is used to make a cow realize that it needs to replenish its bodily what by the body?
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A:
water