# Remix Public Challenge #2 ### Remix Challenges is an onchain quiz that uses a ZK Proof. People submitting answers won't reveal their solutions. - Why not just code the challenge in Solidity? All the data in the Ethereum blockchain is public and visible. This means that if the challenge is coded in Solidity, the first user who finds the solution will submit that solution in **a transaction** and thus the solution will be visible by everyone. Using a ZK Proof, we only require the user to post a **proof** that the challenge has been successfully completed. ## Setup - Go to this repo https://github.com/yann300/remix-challenges - Instructions about how to answer the Challege's questions to generate the **proof** and to mint the badge are here: https://github.com/yann300/remix-challenges#completing-the-challenge ## Challenge Questions 1. What is the CRUD operation you cannot do in Ethereum? (but don't get too clever thinking about the opcodes SELFDESTRUCT or JUMPCALL) 2. What is the EIP number for a non-fungible token? 3. In Remix's Deploy & Run module, what is the name of the first select box - it's where you would choose to connect Remix to a browser wallet. 4. In a ERC 721 contract, there is a function called safeMint. What is safeMint's first parameter? Hint - load up a new workspace in Remix and choose the ERC 721 contract template.