Evaluate the similarity between them and classify them into classes from 0-5 as follows:
0 : The two sentences are completely dissimilar.
1 : The two sentences are not equivalent, but are on the same topic.
2 : The two sentences are not equivalent, but share some details.
3 : The two sentences are roughly equivalent, but some important information differs/missing.
4 : The two sentences are mostly equivalent, but some unimportant details differ.
5 : The two sentences are completely equivalent, as they mean the same thing.

Q: Sentence 1: A man is diving into a swimming pool. Sentence 2: A man is singing into a microphone.

A: 1
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Q: Sentence 1: Scenario A assumes that the CO growth rate accelerates by .%/yr. Sentence 2: It assumes that methane growth rate accelerates by .%/yr.

A: 2
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Q: Sentence 1: UN presses need for major boost in Syrian aid Sentence 2: UN chief presses for major boost in Syrian aid

A:
5
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