Thanks Brian ... Followed your suggestion (quoted below)
and finally got the update to work (sort of) ... but with
these error messages (and a bunch of other problems):
The repository may no longer be available or could not be contacted
because of network problems. If available an older version
Those 2 repositories are from get-deb and are probably not significant
to the system. My biggest concern is that they are pointing at an
Ubuntu 14.04 repository Is your machine running Ubuntu 14.04? If
so, that version stopped being supported in 2019, unless you pay Ubuntu
a subscription