The year appears to be 1951. For a more detailed product history, you can call Ruger at 603-865-2424. Leave a message with the model of pistol you have, the serial number, and a means for them to contact you.
It was manufactured in 1961.
The Ruger Mark I was produced from 1950 to 1981, and serial number 15095 suggests it was manufactured in the early 1950s. Specifically, based on Ruger's serial number records, this firearm is likely from 1952. For a definitive year, it's best to consult Ruger’s factory records or a detailed reference guide on Ruger firearms.
Primarily in the magazines; Mark II has a bolt hol open also
Ruger's website has a sn look up area.
Ruger's web site has sn tables.
Ruger has sn data on their web site.
No
AFIAK, only Ruger knows. You could try asking at RugerForum.com
Ruger's website has a sn function.
If it's a MK II, it will be marked as such.
9
50-200 or so