Your network contains an Active Directory domain named contoso.com. The domain contains a DHCP server named Server1 that runs Windows Server 2012 R2.
You create a DHCP scope named Scope1. The scope has a start address of 192.168.1.10, an end address of 192.168.1.50, and a subnet mask of 255.255.255.192.
You need to ensure that Scope1 has a subnet mask of 255.255.255.0.
What should you do first?（）

Your network contains an Active Directory domain named contoso.com. The domain contains a domain controller named DC1 that runs Windows Server 2012 R2 and a client computer named Computer1 that runs windows 8.
DC1 is configured as a DHCP server as shown in the exhibit. (Click the Exhibit button.)

Computer1 is configured to obtain an IP address automatically.
You notice that Computer1 is unable to obtain an IP address from DC1.
You need to ensure that Computer1 can receive an IP address from DC1.
What should you do?（）