WorksheetsETHEREUM AND SOLIDITY
Total questions: 50
Worksheet time: 30mins
Cryptocurrency is...
virtual money
enigmatic money
money on a bank account
pocketmoney
What is the first type of cryptocurrency?
Bitcoin
Litecoin
Ripple
NEO
Ethereum
Bitcoin was launched in
2018
2015
2011
2009
The creator of Bitcoin is
Bill Gates
Satoshi Nakamoto
Steve Jobs
Sunshuke Nakamura
Cryptocurrency needs
blockchain technology
you
Euro implementation
fair trade
One of the words is NOT a name of a cryptocurrency
Ethereum
Litecoin
Taka
Doge
Blockchain is ....
a big book
a block in the internet
a ledger
transaction between 2 person
_______________ can be any kind of electronic device that maintains copies of the blockchain and keeps the network functioning.
block
nodes
toaken
chains
Which of the following is popularly used for storing bitcoins?
wallet
box
stack
How many Bitcoins will
there ever be?
21 million in 2140
21 million in 2020
14 million 2015
23 million in 2140
How does one acquire
bitcoins?
As payment for goods or
services.
Purchase bitcoins at a
Bitcoin exchange.
Exchange bitcoins with
someone near you.
Earn bitcoins through
competitive bitcoin mining.
all of the above
What is an Ethereum?
Open software platform based upon Blockchain technology
Private software platform based upon Blockchain technology
Technology used in banks
Centralized platform
Who created the solidity language?
Vitallik Buterin
Gavin Wood
Jefrrey Archer
Satoshi Nakamoto
Solidity runs on _____________ ?
Ethereum Virtual Machine
None of the above
Peer networks
Mining
Once a smart contract on the Ethereum blockchain is deployed, it can never be changed again.
Select one:
False
True
What are the environment options in Remix IDE?
Web3 Provider
Web3 Consumer
JavaScript VM
Injected Provider
What are the different units of Ether ?
Select more than one:
milliether
cwei
Gwei
microether
Which among below is a true statement
Select one:
all ethereum accounts are controlled by/can be accessed by their respective private keys
none
startGas is dynamic, subjected to market conditions
. transaction fee depends on the time of execution of a contraction code
What is the gas refunded to the user?
(startGas - gasUsed) * gasPrice
(gasUsed -startGas) * gasPrice
Nothing is refunded to the user, once a transaction is completed
(gasUsed -startGas)
Which tools are we going to use to create dApps and smart contracts?
Postman
Ganache
Remix
Truffle
Which tool are we using to develop and deploy our contracts?
Solidity
MetaMask
Ganache
Remix
Which tool are we using to set up a network and create addresses?
Solidity
MetaMask
Ganache
Remix
What does the Solidity keyword pramga do?
Imports Solidity
Defines the Solidity version
Imports the Metamask account
Connects to the Ganache network
Which are data types in Solidity?
booleans
string
address
list
To be able to call a function from outside the contract, which modifier must you add?
In memory
returns
address
public
You can send ether to an address data type with a contract.
True
False, the recipient must accept the transaction.
False, you have to mine a transaction first.
False, it must be an address payable data type.
In which scenarios is a fallback function triggered?
Contract received ether and no data.
Contract received no ether.
Contract received data but no function matched the function called.
Contract sent insufficient gas.
What effect does a "require" keyword have on an if/else statement when it's false?
It goes to the next function.
It triggers the fallback function.
It stops the contract and returns any unused gas.
It has no meaningful effect.
What is a Solidity?
Programming language for mobile apps
Code in Bitcoin network
Programming language for writing Smart Contracts
Cryptocurrency
What is the primary benefit of immutability ?
Increased efficiency
Tamper-proof
Scalability
Resiliency
Are the parties involved in the block chain transaction anonymous. Answer True or False?
True
False
What are the different hashes in block chain, select the valid ones
Transaction Hash
Private Hash
Root Hash
Block Hash
What are the properties of a Hash Function ? Select more than one answer.
SHA-256
Fixed Length
Non Unique
One-way function
What are the advantages of private blockchain network?
Faster
Open & Transparent
Scalable
Slow
What are the examples of Private Blockchain network?
R3 Corda
Ethereum
HyperLedger Fabric
Bitcoin
What is the correct order of steps in the Bitcoin transaction lifecycle?
Initiate the transaction ,Sign the transaction, Validate the transaction, Broadcast the transaction , Nodes validate the transaction , New Block added to existing Blockchain, Transactions combined to form a data block Transaction is complete the ledger is updated
Initiate the transaction ,Sign the transaction, Validate the transaction, Broadcast the transaction , Nodes validate the transaction , Transactions combined to form a data block , New Block added to existing Blockchain, Transaction is complete the ledger is updated
Initiate the transaction,Validate the transaction, Sign the transaction,Broadcast the transaction,Nodes validate the transaction,Transactions combined to form a data block, Transaction is complete the ledger is updated ,New Block added to existing Blockchain
Initiate the transaction, Sign the transaction,Validate the transaction, Broadcast the transaction,Nodes validate the transaction,Transactions combined to form a data block, Transaction is complete the ledger is updated ,New Block added to existing Blockchain
What are the features of Blockchain ?
Select more than one
Immutability
Centralized
Tamper-proof
Distributed
Who adds a block to the chain?
miner
Node
Block Validator
None
_______is the process of solving complex mathematical equation?
Hash Matching
Genesis
Proof of work
Proof of stake
Bitcoin and Blockchain mean the same thing
True
False
Maybe
I don't know
What does P2P stand for?
Peer to Peer
Private key to Public key
Pineapple to Pizza
Password to Profile
What incentive do miners get for solving equations?
Praise
Access to classified information.
Get computer parts in discount
Rewards usually in terms of crpytocurrency.
What does proof of stake stand for ?
Proof of stake is a system of validation invented by Hal Finney, that enables bitcoin to achieve distributed consensus.
Proof of stake is the consensus algorithm used by bitcoin.
Proof of stake is a type of consensus algorithm by which a cryptocurrency blockchain network aims to achieve distributed consensus. In PoS-based cryptocurrencies the creator of the next block is chosen via various combinations of random selection and wealth or age.
Proof of stake is cryptographic hash-based proof-of-work algorithm that requires a selectable amount of work to compute, but the proof can be verified efficiently.
What are the potential benefits of smart contracts
high contracting, enforcement, and resilience costs
low contracting, higher reenforcement, and compliance costs
low contracting, enforcement, trust, compliance costs
low contracting, enforcement, safe backup, third parties
Which is NOT a common feature of blockchains and cryptocurrencies?
Transparency or privacy
Centralized control
Smart contracts
Hedge against hyperinflation
Which algorithm has the highest computational cost?
Proof of Authority
Proof of Work
Proof of Stake
Function modifier in Solidity
Changes the behaviour of a function
Changes the visibility of a contract
Changes the payment method
All of the above
Address Payable is used
To get the payment
To send the payment
Bith
None
Ethereum was developed by
Satoshi Nakamoto
Galvin Woods
Vitalik Buterin
None of the above
