Discovering Blockchain Technologies

Blocks in Blockchain are interlinked via ...

• hashes

• encryption

• digital signature

• public keys

Merkle root is stored at the...

• block header

• block body

The following are the benefits of Merkle Trees, EXCEPT...

• Able to prove the integrity and validity of data

• Require little memory or disk space

• Small amounts of info to be transmitted across networks during verification

• Data in a Merkle Tree are encrypted

A Bitcoin address is derived from...

• a fixed number

• a public key

• the date and time of address creation

• the encrypted value of a private key

A __ key is needed for signing a transaction.

• public

• private

• door

A __ key is needed to verify a digital signature.

• public

• private

• car

In __, miners have to solve a mathematical puzzle.

• PoW

• PoS

• PoA

• PBFT

The answer for the mathematical puzzle in PoW is the ...

• nonce value identified by a miner

• number of zeros identified by a miner

• root of an equation

Validators in Ethereum are selected ______ to participate in block validation.

• based on node ID

• based on FCFS

• by previously chosen validators

• randomly

To ensure a Bitcoin transaction made would not be reversed...

• it is recommended to run PoW twice

• it is recommended to wait until 6 confirmation arrives for the transaction

• it is recommended to sign the transaction

• it is recommended to pay a high transaction fee