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Interactive Certification

Blockchain Security & Mempool Quiz

Test your mastery of TRC20/ERC20 token mechanics, mempool retention, and anti-fraud protocols. Score 80%+ to earn your verifiable Security Analyst Certificate.

Question 1 of 5

What happens when an unconfirmed (0-conf) transaction lacks sufficient gas/energy fees?

Question 2 of 5

Which 4-byte method ID selector corresponds to the standard ERC20/TRC20 transfer(address,uint256) function?

Question 3 of 5

How many decimal places does the official USDT smart contract use on TRC20 and ERC20?

Question 4 of 5

What is the primary mechanism used on TRON to pay for smart contract TVM execution without burning TRX?

Question 5 of 5

How can a sender replace a stuck pending transaction in Ethereum using Replace-By-Fee (RBF)?