In a situation where a replicated database must be updated, the update operations should be performed in the same order at each copy. a. true b. false A key issue confronting us with clock synchronization is the case of multiple concurrent updates to a database. a. true b. false To ensure updates are made in the same order at each copy of a database, typically: a. a broadcast is used. b. a multicast is used. c. a totally-ordered broadcast is used. d. a totally-ordered multicast is used. Caudal message delivery employs vector timestamps to order messages. a. true b. false In multiprocessor systems, critical regions are protected using semaphores, monitors, and similar constructs. a. true b. false