The first one,,don't know really. I'd guess the 'K' was Kommando (Command). Though it could be Cavalry (Kavallerie(sp?)
There's another possibility for the K,,though I'm not really sure on this one,,and it's that of a Coastal Defense Group.
That may immedietly draw a conclusion that the 'Ar' is for Artillery,,but that's usually just 'A' for field artillery and Af for foot artillery. These WW1 markings are confusing at best as they seem not to follow the rules most of the time.
#2 is I believe Weimar Era Police marking.
'L' is for the Landjagerei (sp?)
A rural police/constabulary force.
The Administrative District (Hi) is Hildeshiem.
The '12' is weapon number. If it had been a Roman Numeral it would have been a Police District or Precinct within the Administrative District of Hildeshiem.
The weapon number will follow the police district numeral if both are present.
This is a Prussian State Police Marking,,1932 to about 1937/38.