Prepare a 1-2 paragraph discussion for each exercise below

Exercise 1: Several other consensus mechanisms exist or have been proposed. For example, Ethereum is planning to switch from the proof of work to a proof of stake algorithm called Casper. Research three other consensus mechanisms not discussed here and explain their potential appeal.

Exercise 2: The maximum number of bitcoin that can be minted is 21 million. Currently, nearly 17 million Bitcoin have been mined but many of these bitcoin have been forever lost as a result of negligence. A recent article in the Wall Street Journal suggested that some desperate individuals have hired hypnotists to help them recover their passwords, as nearly 20% of all bitcoin has permanently vanished from circulation. While the Bureau of Engraving and Printing will help to redeem mutilated US currency, there is no similar recourse for holders of lost cryptocurrencies. Discuss the philosophical implications of restoring stolen funds to their original owners while remaining mindful of the core principles of the Blockchain that emphasize its presumed immutability and lack of a central authority.

Exercise 3: In the days of social payment platforms (e.g. venmo), discuss whether anonymity is a valuable transactional attribute in our society?

Exercise 4: Create an account on stamp.io and then upload any compatible file of your choice. After the file is uploaded, a stampery certificate of proof will be generated within a few hours. Open the stampery certificate and then click on the bitcoin transaction link, "Txid" (located on the bottom right of the screen). Clicking on this link will allow you to observe that the prefix and root information found on the stampery certificate match the information recorded on the blockchain ledger (refer to the output script field). Include a screenshot in your submission. Discuss an example of how time stamping a document on the blockchain could be useful to you.