ADS Questions

1)How do i configure a Additional Domain Controller to share the load with main DC ?

2) While demoting a DC, will it transfer all the operation Masters role to another DC in a domain ? or is it carried out manually ?

3) What would be the effect if the main root domain holding Schema masters & Domain Naming master role crashes ? how do u bring it up ?
4) i have one Additional Domain controller for my root DC, if the root dc fails can i take it offline & bring up the Additional Domain Controller by giving the IP address of root domain that i took offline.