问题：

[多选]

You are the network administrator for Company. 
Five of Company’s employees have Windows 2000 Professional portable computers. The employees use their portable computers in a network enabled docking station when they are at their desks. When the employees are working outside of the office, they use the portable computers without network connectivity. You have just installed wireless PC Card network adapters in the portable computers so that the employees can access the network when they are in conference rooms in the office building. 
You need to configure the portable computers to always allow the employees to choose which network environment to use when they start their portable computers.  
What should you do?（）

A . Configure three different hardware profiles on each portable computer.
B . Configure a single hardware profile and rename it to Universal Profile.
C . Configure the wireless PC Card network adapters to use Automatic Private IP Addressing      （APIPA） when they cannot detect a DHCP server.
D . Instruct each employee to unplug the wireless PC Card network adapter whenever the      portable computer is attached to a network-enabled docking station.
E . Configure the hardware profiles selection to wait until a hardware profile is selected.
F . Configure the hardware profiles selection to select the first profile listed and set the wait time to zero seconds.
G .  Configure the wireless PC Card network adapters to use DHCP to obtain their IP addresses.