See also:

Commands
The Voice Command system understands two types of commands. Universal commands are available at all times. Local commands are available if the supported radio mode is active. ...

Answer or Reject an Incoming Call - Call Currently in Progress
If a call is currently in progress and you have another incoming call, you will hear the same network tones for call waiting that you normally hear when using your mobile phone. Press the button ...

Conference Call
When two calls are in progress (one active and one on hold), press and hold the button until you hear a double beep indicating that the two calls have been joined into one conference call. ...