Problem: Given the question: 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 -
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The answer is:
Water comes into contact with something made of iron


Problem: Given the question: What is the missing first step of the following process:  -  The magma goes into volcanos - The volcanos pressure the magma upwards - The pressure causes the magma to push through the surface of the volcano - The lava cools - The lava forms new rock - New magma is pressured to the surface of the volcano - The volcano bursts through the rock the formed after the last eruption.
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The answer is:
Magma rises from deep in the earth


Problem: Given the question: What is the missing first step of the following process:  -  A selection of grapes are gathered - The grapes are washed - The stems are removed from the grapes - The grapes are crushed and added to a fermation container - Yeast is added to the container - The yeast eats the sugar in the yeast, releasing alcohol -
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The answer is:
