A. The entries for the DNS servers are stored in the registry in the location HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters under the NameServer value, Each entry should be separated by a space. Using the Resource Kit utility REG.EXE the command to change would be as follows
reg update HKLM\System\CurrentControlSet\Services\Tcpip\Parameters\NameServer="18.104.22.168 22.214.171.124" \\<machine name>
where 126.96.36.199 and 188.8.131.52 were the addresses of the DNS servers you wanted to configure. Note it sets the value, it does not append so ensure you enter in the existing DNS servers as well as the new ones.
This may be useful for granting users access to the internet by remotely updating their registry to know which DNS servers to use.