Ethereum Developer Test 1 - Practice Test Geeks

Among the Ethereum addresses, public keys, and private keys, which statement is TRUE?

The address serves as the public key; both are 20 bytes long, whereas the private key is 32 bytes long.

An address is 20 bytes long, a public key is 64 bytes and the private key is 32 bytes

A public key is 32 characters, a private key is 64 characters long, and an address is 20 characters long.

Correct! Wrong!

We can see how addresses are created in the Ethereum Yellow paper's Appendix F. Signing Transactions. First, it is assumed that the sender has a 32-byte private key. Given that we are discussing bytes rather than characters, first option is therefore already incorrect. A 64-byte key, also known as a public key, is produced when we run ECSDAPUBKEY. Therefore, second option is the correct one. The 160 rightmost bits of the public key's Keccack hash constitute the address. To put it another way, the hash's final 40 hex characters, or the right 20 bytes, as 1 byte is 8 bits and 20 bytes are equivalent to 160 bits

In solidity, the outcome of dividing number -5 by integer 2 is

-2.5 as a result of the automated casting or conversion into a float.

Since Solidity only understands unsigned integers, it is not possible.

-2 due to the truncated decimal (rounded to zero)

-3 as it is always rounded.

Correct! Wrong!

Division rounds to zero in solidity. Consequently, it is trancated. Accordingly, int256(-5) / int256(2) = int256 (-2). This time, the answer would be -2. The best answer is therefore the third option.

What does it mean when we say, "A Hashing Algorithm is deterministic"?

Given a lengthy input, it produces the result using equally scattered data.

Given the output, it shouldn't be feasible to generate the input again.

When given the same input, it always generates the same output.

Correct! Wrong!

What functions do private keys represent?

To create a transaction-capable address.

To serve as a cryptographically significant shield for the Public Keys.

To verify signatures on documents and determine an address from.

Correct! Wrong!

What does a transaction's nonce-field imply?

Adding a second checksum to transactions

All ethers sent from that address combined

To defend off replay attacks

Correct! Wrong!

Complete the statement, "DApps are..".

For banks and other large financial institutions, a novel application of logical processes. In this way, they may operate with less people and higher security.

Good, that they eliminate the middleman, operate on a reliable platform, add logic to the blockchain where existing financial assets are already functioning, and so enable peer-to-peer trade.

A great method for developing new applications. These platforms' apps run totally independently of one another and support logical interactions. They are unable to access any money, which adds another element of trust.

Correct! Wrong!

Choose the correct scientific notation?

1 Ether = 10^18 wei, 10^6 Gwei, 10^6 Finney

1 Ether = 10^18 wei, 10^9 Gwei, 10^3 Finney

1 Ether = 10^16 wei, 10^13 Gwei, 10^3 Finney

1 Ether = 10^19 wei, 10^13 Gwei, 10^3 Finney

Correct! Wrong!

It is best to use the blockchain to its full potential...

To only utilize it for purposes that require the advantages of the blockchain.

To apply it to the entire business logic. Having everything in one location is always preferable.

Both statements are correct.

Correct! Wrong!

Which statement is TRUE about Proof of Work (PoW) and Proof of Stake.

PoS mining uses specialized brand-new hardware that must be acquired with a network-wide stack of ether. Thus the name, which comes from Stack and is called Proof of Stake.

PoW has a high energy requirement due to its computational complexity. But at the other hand, mining a block and adding transactions results in a clear reward for the miner.

PoW is superior to PoS since the network uses more energy when PoS is used.

Correct! Wrong!

How many stakeholders made up the DAO?

10000

18000

35000

48000

Correct! Wrong!

What programming language was used to create the Trinity eth2 client?

Python

C++

Cobol

Rust

Correct! Wrong!