Crypto Jobs Blockchain Fundamentals 4

Question 1

In public-key cryptography used by wallets, which key is shared to receive funds?

Accepted Answer

The public key (or derived address)

Answer

The public key or its derived address is shared to receive funds, while the private key stays secret to authorize spending.

Question 2

What does a digital signature prove in a transaction?

Accepted Answer

That the holder of the private key authorized the transaction

Answer

A digital signature cryptographically proves the sender controls the private key without revealing it.

Question 3

What is a Merkle tree used for in a block?

Accepted Answer

Efficiently summarizing and verifying all transactions via a root hash

Answer

A Merkle tree hashes transactions into a single root, enabling efficient and tamper-evident verification.

Question 4

What is the typical meaning of 'finality' in a blockchain?

Accepted Answer

The point at which a transaction is irreversible

Answer

Finality is the assurance that a confirmed transaction cannot be reversed or altered.

Question 5

Why are block confirmations important when receiving cryptocurrency?

Accepted Answer

Each added block makes reversing the transaction increasingly unlikely

Answer

More confirmations mean more blocks built on top, making the transaction harder to reverse.

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