Blockchain CBDE Exam Questions Instant Access

Question 1

Externally Owned Accounts (EoA):

Aare changing their address every time a Transaction is sent because of the nonce.

Bare keeping their address, but on the blockchain a nonce is increased every time they send a transaction to avoid replay attacks.

Answer : A

Question 2

Which is the right order for Denominations?

AWei, Finney, Szabo, Ether, Tether.

BFinney, Szabo, Mether, Gwei.

CGwei, Szabo, Finney, Ether.

Answer : C

Question 3

Events:

Aare stored on chain and are a great way to get a return value when a contract calls another contract.

Bare stored in something like a side-chain and cannot be accessed by contracts.

Care used primarily for debugging exceptions in solidity.

Answer : B

Question 4

Public Keys vs. Private Keys. Which statement is true?

AThe Public Key is for Signing Transactions, the Private Key must be given out to verify the signature.

BThe Private Key signs transactions, the Public Key can verify the signature.

CThe Private Key is to generate a Public Key. The Public Key can sign transactions, the address is here to verify the transactions.

Answer : B

Question 5

To generate a random number:

Ait's good to use the block timestamp, as this is always different.

Bit's good to use the block hash as this is clearly always very different.

Cit's good to use the RANDAO smart contract.

Dit's not possible to have a random number in a deterministic environment such as the Ethereum blockchain.

Answer : C

Question 6

To communicate with an Ethereum node via JavaScript:

Athe library you use must make use of the JSON-RPC Interface of an Ethereum Node.

Bmust Implement the Ethereum Protocol to connect to other Ethereum Nodes.

Cmust use Web3.js, which is closed source to communicate to other Ethereum Nodes.

Answer : A

Question 7

Solidity gets compiled:

Ato bytecode that can't be understood by humans.

Bto bytecodes which are essentially opcodes running instruction by instruction.

Answer : B

Blockchain BTA Certified Blockchain Developer - Ethereum CBDE Exam Questions