It looks like you've partially upgraded Qt, but turned off the precise-updates repository. You can try fixing this by launching the Muon Software Center, going to Settings -> Configure Software Sources, going to the "Updates" tab, and ticking the "Recommended Updates" checkbox.
It looks like you've partially upgraded Qt, but turned off the precise-updates repository. You can try fixing this by launching the Muon Software Center, going to Settings -> Configure Software Sources, going to the "Updates" tab, and ticking the "Recommended Updates" checkbox.