A corporate environment includes an on-premise implementation of Exchange Server 2010 SP1. The company intends to use a cloud-based Exchange Server 2010 SP1 provider to provide email service for the Sales team. All other mailboxes will remain in the on-premise environment. You have the following requirements:

* Ensure that all users can access mailboxes by using corporate Active Directory Domain Services (AD DS) credentials.
* Ensure that all users can access a global address list (GAL) that includes all email addresses. You need to recommend a coexistence solution that meets the requirements.

Which two actions should you recommend? (Each correct answer presents part of the solution. Choose two.)