Depends on what the rifle is, and whether or not you can trace it to the actual manufacturer. Interarms was an importer and distributor - not a manufacturer.
Interarms did not make it. Probably chinese
No way to tell without a detailed description
Serial number
We can't tell without the serial number- but if you go to the Ruger website, under Customer Service, you can see the year of manufacture for serial numbers. You will need the spefic model of your rifle.
Usually by the serial number.
Serial number and features.
Serial number and or proof marks
No way to tell just by the serial number.
First, it would help to figure what the rifle itself is - the serial number does not tell that.
Usually by the serial number.
Not unless you tell if it is a rifle or pistol and who made it.
We can't tell from a serial number alone.