What is a QoS requirement for VoIP calls?

Which action prevent toll fraud in Cisco Unified Communications Manager?

An administrator is trying to change the default LINECODE for a voice ISDN T1 PRI.
Which command makes the change?

An administrator must configure several audio codecs for optimal bandwidth utilization in a large Cisco UCM solution that includes a gateway to ensure audio quality without call failures.
Where must a list of codecs be configured?

An administrator must manipulate a number when a specific criterion is met. If this happens, the administrator wants to route the call again based on the new information to send the call to the correct destination. How must the administrator archive this function in the Cisco UCM?