Value of any gun is based on exact make, model, condition, and variables such as barrel type, sights, etc. We can't tell that from the info you gave use. Most of these sell for at least $100, up to about $400.
Impossible to answer without the serial number.
You can look up the serial number on ruger's website
100-300 USD or so
by serial number
The serial number. Ruger's webiste has extensive serial number data you can pull up. Go to the product history link on that page under customer service tab.
The brand is Sturm, Ruger, not Strum- and we cannot tell without a serial number, However, if you visit the Ruger website, look under customer service, historical data, pistol, you can find your model, and the serial number range for year of manufacture.
50-200 USD
20-200 USD or so
@ 36 years ago
Sturm, Ruger was founded in 1948 by William Batterman Ruger with a $50,000 stake from Alexander Sturm, a family friend and gun collector.
Contact Sturm/Ruger and ask for an archive check. Sometimes a small fee is involved.
50-500 USD depending on specifics