You have an Exchange Server 2003 organization. 
All users connect to their mailboxes by using Microsoft Office Outlook. 
You start to transition the organization to new Exchange Server 2010 servers. The new servers are on a secured subnet that is separated by a firewall. You will move half of the mailboxes to the new servers. 
Client Access servers and Mailbox servers are on the secured subnet. Client computers on the network can access the Client Access servers. 
You need to recommend a solution that allows users to connect to Public Folders by using Outlook orOutlook Web App （OWA）. 
What should you include in the solution？（）

Your company has two main offices named Main1 and Main2.An Active Directory site exists for each office. Users connect locally to servers in both offices. 
The offices connect to each other by using a high-speed WAN link. You plan to deploy Exchange Server 2010. 
You need to plan the deployment of Mailbox servers to meet the following requirements：
.Ensure that users can access their mailbox from a server in their site， if a single Mailbox server fails 
.Ensure that users can access their mailboxes remotely if a site fails 
.Minimize the number of servers
How many Mailbox servers should you include in the plan？（）