A copy of Dieter Marschall's book should help you. Probably 1931-33.
You will need to contact Walther
You will have to contact Walther to find out.
You will need to contact Walther.
1938
@1944
You will can contact Walther, but probably 1943-45.
Impossible to answer without the serial number.
You will have to call S&W to find out.
70-85
To determine the date of manufacture for a Walther Model PP based on its serial number, you would need to refer to specific production records or tables that link serial numbers to dates. Generally, the Walther factory records and various collector guides can provide this information. If you have the serial number, you can often find online resources or forums dedicated to Walther firearms that can assist you in pinpointing the manufacture date.
@ late 70's
Roughly 1940-1945