Which two statements are true about the rescue configuration file?

Creating and Returning to a Rescue Configuration

A rescue configuration allows you to define a known working configuration or a configuration with a known state that you can roll back to at any time. This alleviates the necessity of having to remember the rollback number with the rollback command. You use the rescue configuration when you need to roll back to a known configuration or as a last resort if your router or switch configuration and the backup configuration files become damaged beyond repair.

To save the most recently committed configuration as the rescue configuration so that you can return to it at any time, issue the request system configuration rescue save command:
user@host> request system configuration rescue save

To return to the rescue configuration, use the rollback rescue configuration mode command:
[edit]user@host# rollback rescue
load complete

Note: If the rescue configuration does not exist, or if the rescue configuration is not a complete, viable configuration, the rollback command fails, an error message appears, and the current configuration remains active.

To activate the rescue configuration that you have loaded, use the commit command:
[edit]user@host# rollback rescue
load complete
[edit]user@host# commit

To delete an existing rescue configuration, issue the request system configuration rescue delete command:
user@host> request system configuration rescue delete
user@host>

For more information about the
request system configuration rescue delete
and

“request system configuration rescue save “commands, see the CLI Explorer.

http://www.juniper.net/documentation/en_US/junos14.1/topics/task/configuration/junos-software-rescue-configuration-creating-restoring.html