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The function proposeUSDPrice() incorrectly uses only one price for all token contracts. This is incorrect since token contracts e.g. WETH and USDB have different USD prices. This can cause prices to be set incorrectly for token contracts and thus weighted value of the locked tokens during schnibble calculation ends up being incorrect. 
The issue is being marked as low since although the functionality of the protocol is impacted, the root cause arises from the assumption that price feed roles are not aware that all token contracts share the same price and pass in incorrect parameters. 
Solution: Either take in a single token contract as the input parameter or multiple prices i.e. an array as done with the _contracts parameter currently.
