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.

[EX Q]: Sentence 1: Liquid ammonia leak kills 15 in Shanghai Sentence 2: Liquid ammonia leak kills at least 15 in Shanghai
[EX A]: 5

[EX Q]: Sentence 1: NYPD Twitter Outreach Backfires Badly Sentence 2: NYPD's twitter campaign backfires
[EX A]: 5

[EX Q]: Sentence 1: The government has chosen three companies to develop plans to protect commercial aircraft from shoulder-fired missile attacks, homeland security officials announced Tuesday. Sentence 2: The Department of Homeland Security announced Tuesday that it has selected three companies to continue research into ways to thwart shoulder-fired missile attacks on U.S. commercial aircraft.
[EX A]:
5