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.

Sentence 1: Umm the California was a cargo ship I dont care what the article says. Sentence 2: The California was a cargo ship.
4

Sentence 1: Residents return to Texas blast site Sentence 2: Residents return to Fallujah
0

Sentence 1: No. 2 HP saw its Unix server sales dropped 3.6 percent to $1.36 billion. Sentence 2: HP fell to second place with server sales growing 0.4 percent to $2.9 billion.

2