Welcome to the forum!
I took an immediate interest in the cover with the 5 stamps on it, and as you're a newcomer to the field I wanted to point out a few things of importance. Let's start with the 2¢ stamp on the right (E). You can well imagine that a postal clerk would have applied this marking in such a way that it tied the stamp to the envelope it originated on. The green line I added is just one indication of this. ("Tied to cover" is the term commonly used to describe this.) But not so for the other stamps which, by the way, were produced many years later than the 2¢ stamp. Note how the 10¢ stamp has a circular cancel that does tie to the circular cancel underneath it, or to stamp E. Also, the wording in the stamp's cancel is at 90º to the text of the cancel underneath it. The date-of-issue discrepancy between that stamp and stamp E aside, those factors indicate that stamp D did not originate on that cover.
Stamp C sports a wavy line style cancel that also does not tie to the cover. We have similar situations with stamps A and B.
So it looks like someone was having fun with that cover, adding more contemporary stamps to it after-the-fact. So chances are that that cover isn't of much value, but if nothing else it's a lesson in identifying stamps that originate (and not) on cover.