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: The baby is laughing and crawling. Sentence 2: A baby is laughing and crawling on the floor.

A: 4
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Q: Sentence 1: Under NASD regulations, Mr. Young can file a response and request a hearing before an NASD panel. Sentence 2: The analyst, already let go by Merrill, can request a hearing before a NASD panel.

A: 3
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Q: Sentence 1: The tech-heavy Nasdaq composite index fell 3.99, or 0.2 percent, to 1,682.72, following a two-day win of 55.93. Sentence 2: The technology-laced Nasdaq Composite Index .IXIC eased 8.52 points, or 0.51 percent, to 1,670.21.

A:
2
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