Beginner's question: Are the Kubuntu-PPA's being in use?

[Volker Wysk]

Hi!

I'm new to (K)Ubuntu (but not new to Linux at all). I've installed the 
Kubuntu-PPAs with these commands:

apt-add-repository ppa:kubuntu-ppa
apt-add-repository ppa:kubuntu-ppa/backports

This has installed kubuntu-ppa-ubuntu-backports-wily.list and kubuntu-ppa-
ubuntu-ppa-wily.list in /etc/apt/sources.list.d.

But they don't seem to be in effect to me. There is no line with "kubuntu" in 
it, in the output of "apt-get update". And KDE doesn't seem to have gotten 
updated (doing apt-get dist-upgrade).

I've studied the following articles:

https://wiki.ubuntuusers.de/Paketquellen_freischalten
https://wiki.ubuntuusers.de/Paketquellen_freischalten/PPA

I've also tried the muon-updater / software-properties-kde commands, which 
seem to indicate that everything is working.

So, how do I check if the Kubuntu-PPA's are in effect?

Thanks,
V.W.