Which command will show you whether a DTE or a DCE cable is plugged into serial 0?

You want to totally reinitialize the router and replace the current running-config with the current startup-config. What command will you use?

If you delete the contents of NVRAM and reboot the router, what mode will you be in?

What is the problem with an interface if you type show interface serial 0 and receive the following message? "Serial0 is administratively down, line protocol is down."