Your company has a main office and a branch office. The main office contains two domain  controllers.    
You create an Active Directory site named BranchOfficeSite. You deploy a domain controller in  the branch office， and then add the domain controller to the BranchOfficeSite site. 
You discover that users in the branch office are randomly authenticated by either the domain  controller in the branch office or the domain controllers in the main office.  
You need to ensure that the users in the branch office always attempt to authenticate to the  domain controller in the branch office first.    
What should you do（）

Your network contains two Active Directory forests. One forest contains two domains named  contoso.com and na.contoso.com. The other forest contains a domain named nwtraders.com. A  forest trust is configured between the two forests.    
You have a user named User1 in the na.contoso.com domain. User1 reports that he fails to log  on to a computer in the nwtraders.com domain by using the user name NA\User1.    
Other users from na.contoso.com report that they can log on to the computers in the  nwtraders.com domain.    
You need to ensure that User1 can log on to the computer in the nwtraders.com domain.    
What should you do（）