Problem: What is the missing first step of the following process: - The water combines with carbon dioxide in the air to form carbonic acid - As the acid is formed, the iron starts to dissolve - Some of the water breaks down into hydrogen and oxygen - The free oxygen and dissolved iron bond together - They form iron oxide, which is rust -

A: Water comes into contact with something made of iron

Problem: Given the question: What is the missing first step of the following process: - Green house gases enter from the earth - Heat is trapped in atmosphere - Different things on earth are hotter - The overall planet is hotter.
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The answer is:
Suns heat enters atmosphere

input question: What is the missing first step of the following process: - The earth changes energy from the sun into heat - Heat rises from the ground - Greenhouse gas molecules in the atmosphere prevent the heat from going into space - The temperature of the earth increases - The temperature continues to rise and melts the polar ice caps - The temperature rises even faster.???
output answer: Greenhouse gases are released into the air by human activities

What is the missing first step of the following process: - The soft tissue decomposes - The bones are left behind - Scavengers tear the body apart and move the bones elsewhere - Wind and rain also scatter the bones further - The bones left behind will weather and become buried by sand and soil - The proteins in the bone are replaced with minerals that are dissolved in the soil - This creates a rock-like substance called a fossil - Water and wind erosion wear away the layers of soil on top of the fossil - This makes discovery of the fossil possible.
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Answer: The organism must die to begin the process

Q: What is the missing first step of the following process: - Food is squeezed down the esophagus when you swallow - Acid and enzyme in the stomach break the food down - Releases nutrients - Food then pumped into small intestine - Fluid and enzymes from liver and pancreas pumped into small intestine - Help break food into smallest molecules - Nutrients pass through wall of small intestine - Nutrients absorbed into blood stream - Unused materials passed into large intestine to become fecal matter.
A: An enzyme in saliva begins to break down carbohydrates

[Q]: What is the missing first step of the following process: - The spores fall to the ground - The spores germinate - The spores begin to grow mycelium - The mycelium begin to sprout a bud - A new mushroom is formed.
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[A]:
Spores are dispersed into the air by a mature mushroom