10) What are the four properties of transactions in relational database systems? [2/40] 11) Briefly describe how to test conflict serialisability of a schedule. [2/40] 12) Briefly describe how to determine if a schedule is cascadeless. [2/40] 13) Briefly describe the two-phase locking protocol for concurrency control in relational database systems. [2/40] 14) In log-based recovery algorithm, what is meant by 'undoing' and 'redoing' a log record of the form ' ', where T stands for a transaction, X for the data item, and V for values? [2/40] 15) Describe what a recovery system would do when performing checkpointing. [2/40]