I have to do some research on what a "merkle root" is. I am not asking about difficulty, I am asking about each individual blocks solution.
merkle root is a merkle tree of all transactions it is calculated hashing all transactions:https://bitcoin.org/en/developer-reference#merkle-trees
Are there multiple solutions to a block?
yes, but when you find the first solution you wil start mining a new block. You don't have to find another solution.