1. Which of the following operation is not supported by bitcoins script language? A. Adding two number B. Conditioning (if/then) C. Hashing D. Looping

2. Alice is paying for millisecond-by-millisecond video streaming using bitcoin micropayments. If she simply disconnects at some point without notice and stops sending micropayments. What can the streaming company do? A. The company is out of luck. It does not earn any bitcoins and must pursue legal recourse B. The company can redeem the last micropayment transaction Alice sent before disconnecting, which matches the length of service she had received C. The company can redeem the maximum amount that Alice initially escrowed into a multisig address D. The company can refuse to sign the refund transaction, so both Alice and the company will end up losing Bitcoins, which will sit in a multisig escrow forever

3. A traditional Byzantine fault tolerance broadcast problem does NOT require that A. All honest nodes eventually agree on the same value B. All honest nodes eventually agree on the leader s value if the leader is honest C. All malicious nodes eventually agree on the same value D. The protocol does not run forever

4.Proof-of-burn has been used or proposed to be used in all the following settings except for A. Exchange bitcoins for tokens in an initial coin offering B. Destroy undistributed tokens in an initial coin offering C. Slash (punish) misbehaving nodes in a proof-of-stake system D. Pruning old spent transactions to reduce the blockchain size

5. Which of the following technology do you expect Open Bazaar, a cryptocurrency version of e-Bay, to adopt in order to allow escrows to resolve e-commerce disputes? A. Multisig transactions B. Proof of burn C. Sharding D. Lightning

6.Which technology among the following is most distinct from the other three A. Efficient micropayments B. Lightening C.Payment channel D. Casper