Chapter 5 assessment 1

1. What calculations is a Turing complete machine limited to?

   • It is limited to simple arithmetic

   • It can calculate complex mathematics but is not useful for things such as machine learning

   • It can perform any type of calculation within the bounds of the bit width of the CPU architecture on which it runs (e.g. 64 bits)

   • There are no limits. <-

2. What part of the Bitcoin system is analagous to the tape in a Turing machine?

   • The scriptSig is the tape

   • Each transaction is a separate tape

   • The ledger is the tape <-

   • The chain of block headers is the tape

3. What is the maximum length of an ECDSA signature in Bitcoin

   • 72 bytes

   • 73 bytes <-

   • 74 bytes

   • 75 bytes

4. What determines the length of the scriptPubKey element used in the formation of the transaction pre-image?

   • The length of the script in the output being spent

   • The size of the parent transaction

   • The placement of the preceding OP_CODESEPARATOR opcode within the scriptPubKey <-

   • The satoshi value of the input