CBDE

CBDE practice questions, page 4 of 4, with answer review and explanations.

Question 16

Smart Contracts:

  1. are always living on the same address, because the blockchain is deterministic. So, one account can always have one smart contract.
  2. are having the same address as the EOA.
  3. are sitting on their own address. The Address is created from the nonce and the EOA address and could be known in advance before deploying the smart contract.
  4. the address of the smart contract is a random address which gets generated by the miner who mines the contract-creation transaction.

Question 17

Transactions containing the same data to create the same smart contract are:

  1. always having the same signature.
  2. having a different signature because of the nonce which changes upon every transaction.

Question 18

Sending one Ether is actually internally translated:

  1. to Wei, so it will send the equivalent of 10^18 Wei.
  2. to Finney, so it will send the equivalent of 10^3 Finney.
  3. to Szabo, so it will send the equivalent of 10^6 Szabo.

Question 19

Hashing Mining uses:

  1. Keccack256 while internally to hash values it's easy to use the Dagger-Hashimoto to create a meaningful hash.
  2. the Dagger-Hashimoto hashing while internally the EVM uses SHA256 which is an alias for Keccack256.
  3. the Dagger-Hashimoto hashing while internally the EVM uses Keccack256 which is almost similar to SHA256, but has a different padding so produces different hashes.

Question 20

PoS:

  1. would be better, because it can reduce the amount of energy needed for mining.
  2. would be worse, because it would increase the amount of energy needed for mining.