Language-Sensitive fields and Related Language Records

I have several questions related to the language-sensitive fields and related language records:

What columns are considered to be language-sensitive.
How does PeopleSoft decide whether a particular column of a table is or is not language-sensitive?
Would any non-numeric and non-date fields be considered to be language-sensitive? Typically short-description, long description, longname, shortname are considered to be language-sensitive. Why are Translate value and Prompt table editable codes considered not to be language sensitive?
Is it a matter of choice whether any given table should have a related language table? In other words, is it technically possible for a table having only numeric columns, for example, to be defined to have a related language table? If so, what would be fields of such a related language table?
Can any one of the Peopletools tables (the ones beginning PS) have related language tables? Is this a technical feasibility?
Can any one of the application tables (the ones beginning PS_) have related language tables? For example, suppose there is only a key field and only non-language-sensitive fields in a certain base table, is it possible for such a table to have related language table defined? Even if this is technically possible, would it make sense?

Any inputs would be very helpful.