Problem: Given the question: What is the missing first step of the following process:  -  The magma cools - Crystals form and the magma become igneous rocks - The igneous rocks break down into sediment - Become sedimentary rocks - If subjected to heat and/or pressure from plate-tectonic activity the sedimentary rocks become metamorphic rock - The metamorphic rocks melt - Become magma again.
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The answer is:
Rock begins as magma from a volcano


Problem: Given the question: What is the missing first step of the following process:  -  The coal is broken down to a smaller material - The coal particles mix with hot air and move in to a boiler - Water in the boiler is pumped and produces steam with the coal - Steam powers turbine blades, which magnetically charge wire coals - The water returns back in to its chamber and the process is repeated -
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The answer is:
A type of coal must be chosen before the heating can start


Problem: Given the question: 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.
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The answer is:
