Some doubts about mining mechanism I have some questions about the mining mechanism.

1) After the block has been mined (and the miner found the nonce for the proof of work) the block is broadcast to the network. Are the transactions in the mined block also verified by the other nodes in the network, after checking the correctness of the nonce by the network?

If so, how many confirmation nodes are needed to say "Yes, this mined block contains correct transactions! Let's add it to the blockchain"? If it isn't so, can a miner mine a block with incorrect transactions and then broadcast it into the network?

2) Can a well mined block be rejected by the network? Maybe by some malicious host ?
Well, are the transactions in the mined block verified also by the other nodes in the network, after checking the correctness of the nonce by the network?


Yes.


  If so, how many confirmation nodes are needed to say "yes, this correct mined block contains correct transactions! let add it to the blockchain"?


It doesn't work that way. If a node thinks a block is invalid, it doesn't relay the block. If all nodes who got the block in first place, thinks that the block is invalid, other nodes don't receive that block and it gets forgotten. If they think the block is valid, the clients add the block to their blockchain and relay it to other nodes.


  Can a well mined block be rejected by the network? Maybe by some malicious host ?


Yes, ISPs can do that (although big pools run their own ISP). But that's pretty hard (impossible) without the help of the miner's ISP.