username~$ sudo apt-get install palemoon
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
0 upgraded, 1 newly installed, 0 to remove and 289 not upgraded.
Need to get 0 B/36.7 MB of archives.
After this operation, 104 MB of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
Install these packages without verification? [y/N] n
E: Some packages could not be authenticated
Any ideas? I've tried a few solutions from google and they didn't help. Ubuntu 16.04