User Activity

Why does eBay give me a conversion rate from US to CDN very different from PayPal? I recently won an item @ $355.00US ($349.92CDN). Shipping was $12.00US ($11.83CDN). Total by eBay was $367.00US ($361.75CDN). Why was I charged$371.28CDN by PayPal whe...
Can I retract my feedback given to a seller that I have purchased from? If yes how do I do it? Thank you.
When I make two purchases from the same seller days apart the feedback is calculated as one. I made two separate payments and charged separate shipping...etc.