Which elements of a block are hashed? Other than the previous block hash and nonce data, which elements of a block are concatenated in order to be hashed?
The whole block header is hashed including: 


Block version number
256-bit hash of the previous block header
256-bit hash based on all of the transactions in the block (hashMerkleRoot)
the current timestamp as seconds since 1970-01-01T00:00 UTC
Bits (updated when he difficulty is adjusted)
Nonce


https://en.bitcoin.it/wiki/Block_hashing_algorithm