What is a Transaction?

[elkin2228]

I am currently a Top Rated Seller, trying to stay above the 100 transaction minimum, and I am still not clear with regards to ebay's definition of a "transaction." 

Here are my questions:

#1. If I sell 2 separately listed items to one buyer, and he makes one Paypal payment for the 2 items, and the items are invoiced and shipped together, is that 2 transactions or 1?

#2. If I sell 2 separately listed items to one buyer, and he makes 2 separate Paypal payments for the 2 items (doesn't wait for an ebay invoice), and the items are shipped together, is that 2 transactions or 1? 

#3. If I sell 2 separately listed items to one buyer, and he makes 2 separate Paypal payments for the 2 items (doesn't wait for an ebay invoice), and the items are shipped separately, is that 2 transactions or 1?  This can happen when the 2 purchases are made over a period of a couple of days. 

#4. If the answer to any of my questions is only 1 transaction, the how many days separation must occur for one buyer to purchase 2 items and I am given 2 transactions?

Sorry if this is confusing, but ebay makes if that way.  It would be so much more easier if 1 sale=1 transaction. I don't know of anyplace to get this information from ebay, so I am relying on the community.