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This quiz will check your understanding of Lecture 3.

In accordance with the Coursera Honor Code, I (Anonymous Student) certify that the answers here are my own work.

Question 1

In a typical transaction: (check all that apply)

There is one signature that covers all the outputs

Each input contains a signature

Each output contains a signature

There is one signature that covers all the inputs

Question 2

Bitcoin’s script supports instructions whose effect is: (check all that apply)

Question 3

Alice is paying for a service using Bitcoin micropayments. If she simply disconnects at some point without notifying Bob and stops sending micropayments, what can Bob do? (check all that apply)

Bob is out of luck. He doesn’t earn any Bitcoins and must pursue legal recourse

Bob can redeem the maximum amount that Alice initially escrowed into a multisig address

Bob can redeem the latest micropayment transaction that Alice sent in the last time period before disconnecting, which matches the length of service she received

Bob can refuse to sign the refund transaction, so both Alice and Bob will end up losing Bitcoins, which will sit in the multisig escrow forever

Question 4

Bitcoin micropayments require the use of: (check all that apply)

Multisignature transactions

Proof of burn

Time-locked transactions

Pay-to-script-hash

Question 5

Blocks contain a tree of transactions instead of a flat list because: (check all that apply)

It results in smaller blocks

It’s easier to insert or delete new transactions while the block is being assembled

It enables efficiently proving that a transaction is included in a block

Question 6

If two conflicting transactions A → B and A → C are both broadcast almost simultaneously from different nodes, what determines which one will eventually end up in the block chain? (check all that apply)

The transaction that reaches the majority of nodes first will win

The transaction that was broadcast first will win

The miner who finds the next block will likely resolve the tie by including one of the transactions in the block

Each node has its own version of the block chain containing the transaction that it heard about first

Question 7

Which of the following requires a hard fork? (check all that apply)

Disabling the OP_SHA1 instruction

A requirement that each transaction have its outputs sorted by value in ascending (or non-decreasing) order

Increasing the maximum permitted size of blocks

Decreasing the maximum permitted size of blocks

In accordance with the Coursera Honor Code, I (Anonymous Student) certify that the answers here are my own work.

You cannot submit your work until you agree to the Honor Code. Thanks!

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Bitcoin and Cryptocurrency Technologies

Bitcoin and Cryptocurrency Technologiesby Arvind Narayanan

Lecture 3 Quiz Help Center

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Bitcoin and Cryptocurrency Technologies
by Arvind Narayanan