EMT Practice Test

1. Question Content...

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Question1: The ____________of the tree is the topmost node and hence this tree is represented upside down. The bottommost nodes are called as ________nodes. Each node is simply a cryptographic hash of a transaction.

In the above diagram, Transaction A,B, C,C from the leaves of the tree. Select one.

Question2: When you are developing with Fabric Composer which of the following is true?

Question3: Contracts live on the blockchain in an Ethereum-specific binary format called _____________?

Question4: Which of the following is considered the most popular public key encryption algorithm?

Question5: You would like to run Ethereum DApps in a browser without a node. (No need to download blockchain.) What could you use locally in your Chrome browser?

Question6: The gas price is a value set by the creator of the blockchain transaction? Select best answer.

Question7: Which of the following is NOT considered a token?

Question8: Smart Contracts provide all the following benefits EXCEPT?

Question9: What type of peer node executes transactions?

Question10: You are currently consulting with an organization that ships widgets overseas. They would like to implement a Hyperledger Fabric and would like to know about how to use cryptocurrencies with Hyperledger Fabric.
What is the best answer?

Question11: In Hashcash, miners all compete to look for a so called. "____________"which, if provided as input (together with other parts of a block header) to a hash function, yields an output that's numerically small enough to claim the next block reward.

Question12: ___________________ensures that the shared ledgers are exact copies, and lowers the risk of fraudulent transactions, because tampering would have to occur across many places at exactly the same time.

Question13: Blockchain provenance is defined as _______________?

Question14: What is the difference in using Go-Ethereum over Ganache?

Question15: Ethereum currently uses the ___________Consensus Algo and in the future it is planned to go to the
__________Consensus Algo?

Question16: Which of the following enterprise blockchains have a pluggable framework consensus algo? (Select two.)

Question17: When specifying blockchain technologies, it is important to understand its benefits and its challenges.
What would be two challenges of blockchain technology adoption to an enterprise? (Select two.)

Question18: When writing and considering push and pull in a smart contract that involves "user" funds would it be better to ____________________?

Question19: A ____________cipher basically means it is using a fixed key which replaces the message with a pseudorandom string of characters. It is basically the encryption of each letter one at a time.
What is the cipher type?

Question20: In Ethereum how is the block difficulty determined in Ethereum?

Question21: When considering tokens on the Ethereum Blockchain what is the main difference between ERC20 and ERC721 tokens?

Question22: When developing in Ethereum which is considered to be an In-Memory Blockchain simulations for rapid development?

Question23: Blockchains are decentralized ledgers which, by definition, are not controlled by a central authority. Due to the value stored in these ledgers, bad actors have huge economic incentives to try and cause faults.
What algo was the original solution to the potential problem as specified by Satoshi?

Question24: Looking the graph below, what type of an attack is this likely?

Question25: You are using Truffle for an Ethereum contract and would like to use a default set of contracts and tests from within an empty project directory.
What is the syntax?

Question26: Fabric Ledger has two specific parts. Select answer with the proper two parts.

Question27: Gas has multiple associated terms with it: Gas Prices, Gas Cost, Gas Limit, and Gas Fees. The principle behind Gas is to have a stable value for how much a transaction or computation costs on the Ethereum network.
Which is considered to be the static value for how much a computation costs in terms of Gas?

Question28: Smart Contracts are generally written in specific programming languages. Which one is NOT a language for smart contracts?

Question29: What is the language that Solidity is using to build on the Ethereum Virtual Machines(EVM)?

Question30: Hyperledger is an enterprise focused blockchain project. This project was released by a consortium under the umbrella of the Linux Foundation's Hyperledger Project.
What year did Hyperledger go live?

Question31: With Hyperledger Fabric ledger, it supports both levelDB / CouchDB for state data?

Question32: Hyperledger Composer has following two main components?

Question33: ___________is advantageous because it presents scalability and low cost transactions, but like DPoS introduces a component of centralization.
What algorithm is being referenced here?

Question34: In Hyperledger, nodes need a ________________ to be able to communicate to the network.

Question35: What is a logic gate in electronics and computer science?

Question36: Your customer is an enterprise that is focused on financial sectors. What type of blockchain would this customer likely want specified for their enterprise?

Question37: You currently on a conference call with an executive from a too big to fail bank. They are validating that they want to use Quorum or another enterprise blockchain. They specifically want to know what type of consensus algo it uses and what industry for the Quorum blockchain targets.

Question38: You are considering writing a smart contract for Ethereum and would like to use a robust programming language.
Which programming language is considered the most flexible and robust for Ethereum?

Question39: The difference between Ethereum tokens and a standalone currency like Litecoin is that
___________tokens piggyback on the Ethereum network, hosted by Ethereum addresses and sent using Ethereum transactions.

Question40: An _____________ is a well-known service that signs transactions if they state a fact and that fact is considered to be true. They may optionally also provide the facts.

Question41: R3 Corda does not organize time into blocks. What does Corda actually perform and use?

Question42: Secure Hash Algorithm (SHA-256) output is always 256 bits or 32 bytes in length regardless of the length of the input (even if input is millions of bytes). Select best answer.

Question43: Your company working for is now considering the blockchain. They would like to perform a POC with R3 Corda. The CIO was reading about different blockchain consensus algos and would like to understand what type of consensus algos is used with Corda.
What is the best answer?

Question44: There are two types of tokens in blockchain solutions. (Select two.)

Question45: In the EVM every account has a persistent key-value store mapping 256-bit words to 256-bit words called
________

Question46: In Ethereum the difficulty adjustment algorithm is coded in the ___________ file.

Question47: What component on the blockchain maintains the "world state"?

Question48: The key difference between encryption and hashing is that encrypted strings can be reversed back into their original decrypted form if you have the right key?

Question49: What are two specific advantages of using Hyperledger Fabric? (Select two.)

Question50: Regarding Ethereum contracts, the contracts can call (perform) two specific message calls. The message calls are either _____________ or __________? (Select two.)

Question51: The most popular Ethereum development framework is currently Truffle.
What are three features of Truffle? (Select three.)

Question52: Composer Modeling Language is an object-oriented modeling language that defines the domain model for a business network definition. The modeling language is saved as a
__________ file.

Question53: You have flown to NYC to have a discussion with a technical executive of a too big to fail bank. You are having a discussion about blockchain algos and the customer is asking what are some disadvantages of using a POW algo?

Question54: How many peers in the network need to endorse a transaction in a Hyperledger Fabric blockchain?

Question55: Addresses on a blockchain are derived by a process of hashing _________.

Question56: A centralized system is one that that is governed by a hierarchical authority. Which of the following Blockchains would be correctly stated as centralized?

Question57: A Byzantine failure is the loss of a system service due to a Byzantine fault in systems that requires________.
What is required?

Question58: What type of "bug" generally occurs when something isn't right according to business requirements?

Question59: What does the 20 in ERC20 mean or relate to?

Question60: Ethereum is considered to be a ______________type of blockchain.

Question61: What type of encryption is shown below and is commonly used in blockchain cryptography?

Question62: In what year did a whitepaper that was published by "Satoshi Nakamoto" outlined a solution to the Byzantine Generals problem?

Question63: In the Proof of Stake(POS) algorithm the miners are really known as ___________?

Question64: Chaincode is a decentralized transactional program, running on the validating nodes. As with every chaincode, it implements the ____________________ in particular, Init and Invoke functions.
What does is actually implemented?

Question65: Your company is looking to develop a new token and raise funds for this new platform.
What is the process your company would like go thru to raise funds?