Getting Started Knowledge Check

I’m having trouble getting the root flag on the knowledge check in getting started. I obtained a meterpreter shell using getsimple exploit, then used sudo su to obtain root privileges. When I say whoami, I am root user. I used locate root.txt, but the file that came up was a word list. How do I get to the root.txt flag. Why am I root user, but do not have access to this file?