Problem: Given the question: What is the missing first step of the following process: - Over long periods of time rain can hit the limestone - And cause a acidic reaction - The limestone will slowly disintegrate - A large gap with be where the limestone was - Result in the cave.
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The answer is:
Some of the rock in the ground is made of limestone

input question: What is the missing first step of the following process: - The matter forms on the sea floor - Layers of sediment form above the matter compressing it - After many years the matter is compressed and heated - The result is that crude oil forms.???
output answer: Living organisms in the sea die

What is the missing first step of the following process: - Ocean water pulls sand off of beaches - Ocean water breaks rocks off of cliffs - Ocean water carries sand and rocks into the ocean - Sand and rocks go to other land or the bottom of the ocean.
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Answer: Ocean waves hit land

Q: 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.
A: A bird hatches from an egg

Question: What is the missing first step of the following process: - Bread absorbs water from the air - Bread absorbs warmth from the air - Dust particles with mold spores fall on bread - Mold spores start to consume the bread for energy - Mold colonies grow until they are visible.
Answer: Bread is exposed to the elements

Please answer this: What is the missing first step of the following process: - The pollution negatively affects the water quality - The pollution negatively affects the health of plants and animals - The plants and animals have shorter, less healthy lives - The plants and animals do not reproduce very well - The number of plants and animals decreases over time - The quality of water gets worse and worse as there are no plants or animals to clean it - Eventually there is nothing living in the water and it is unusable -
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Answer:
Pollution enters natural water sources such as rivers and lakes