For each of the following locking protocols, assulning that every transaction follows that locking protocol, state which of these desirable properties are ensured: serializ• ability, conflict-·serializability, recoverability, avoidance of cascading aborts. 1. Always obtain an exclusive lock before writing; hold exclusive locks until end-of-transaction. No shared locks are ever obtained.
2. In addition to (1), obtain a shared lock before reading; shared locks can be released at any time.
3. As in (2), and in addition, locking is two-phase.
4. As in (2), and in addition, all locks held until end-of-transaction.

answer; kayla should use the " save as" command;

answer(true);

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