Refer to the exhibit.

The HQ site uses area code 650. The BR1 site uses area code 408. The long distance national code for PSTN dialing is 1. To make a long distance national call,an HQ or BR1 user dials access code 9, followed by 1, and then the 10-digit number. Both sites use MGCP gateways. AAR must use globalized call routing using asingle route pattern. Assume that all outgoing PSTN numbers are localized at the egress gateway as shown in the exhibit. What should the AAR group prefix be?