If you notice the ranking is not consecutive with the use of the RANK function; that is because the RANK function ranks records of the result-set sequentially starting from 1. When it finds a tie it assigns the same rank to the all the records in the tie, but still keeps incrementing the record counter so the next record will get a new rank which would be (previous rank + no of records in the current tie + 1) .
Implausibility definition, not plausible; not having the appearance of truth or credibility: an implausible alibi. See more.
Proof of impossibility. A proof of impossibility, also known as negative proof, proof of an impossibility theorem, or negative result, is a proof demonstrating that a particular problem cannot be solved, or cannot be solved in general. Often proofs of impossibility have put to rest decades or centuries of work attempting to find a solution.