Two features of hashing are determinism and non-invertibility.

Explain how determinism and non-invertibility are used to facilitate the use of the blockchain.

Award [6 Max]

Determinism:
The hash algorithm must always generate the same output for the same input;
when replicated on different nodes;
Otherwise, the consensus cannot be reached;

Without determinism different miners would get different results;
And there would be no consensus;
So, the distributed ledger would be different for every node;

Without determinism one block could not link to the next / prevHash;
Therefore, transactions could be edited / blockchain would not be immutable;
The blockchain would be insecure;

Merkle tree and the block are validated many times by miners;
Without determinism the Merkle proof won’t work;
So, transactions can’t be validated;

Without determinism, when a sender signs a transaction, other nodes on the blockchain wouldn’t be able to be certain it was them;
Which may result in an increase in illegal payments and corruption;

Non-invertibility:
A public key is hashed to provide a unique encrypted public address that can be published;
Whereas private keys are not publishable and can be hashed (needed to access the wallet);
Non-invertibility guarantees that publishable information is protected, and separated from private key;

Prevents the private key from being calculated if you have the public key;
Non-invertibility/secure private key prevents false transactions being made;
So that “digital signatures” can authenticate the person who made the transactions;

If the nonce used an invertible hash it could be calculated;
So, it would be solved quickly / difficulty level could not be set;
And fake branches could be created / double spend could occur;

Mark as 3 and 3.
Award [1 max] for definition + [2 max] for explanation, for both sections (determinism and non-invertibility)