input question: What is the missing first step of the following process: - People burn coal for heat or electricity - Pollution from the coal goes into the sky - Coal pollution enters clouds - Clouds rain over an area - The polluted rain becomes acid rain.???
output answer: People dig up coal from the ground

What is the missing first step of the following process: - There is a lot of pressure on the Sun - The pressure forces atoms of hydrogen to fuse together in nuclear reactions - The energy from the reactions gives off different kinds of light - The light travels to the Earth.
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Answer: The gravity of the sun pulls its mass inward

Q: What is the missing first step of the following process: - The caterpillar eats constantly until it grows bigger - The caterpillar starts to form a cocoon around itself - The caterpillar becomes a pupa - After some time the cocoon hatches - And a butterfly is born.
A: A larva is born

Question: What is the missing first step of the following process: - The oxygen passes through the bronchial tubes to the lungs - The oxygen is moved into the bloodstream - Circulates through the body - The cells in the body exchange the oxygen with carbon dioxide - The bloodstream carries the carbon dioxide back to the lungs - The lungs expel the carbon dioxide through the nose and mouth.
Answer: A person breathes in oxygen

[Q]: What is the missing first step of the following process: - Through warming or other methods a chunk is taken off the glacier - The chunk drifts into the sea - And it settles where it can remain in its state - It is considered an iceberg.
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[A]: You start with a glacier

Problem: Given the question: What is the missing first step of the following process: - The bird is nurtured by its parents - And is fed food for growth - The bird grows - Begins to learn how to fly - The bird matures - The bird leaves its nest - The bird makes its own nest.
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The answer is:
A bird hatches from an egg