98 cents is the airmail rate.
That would depend on where you are sending it FROM.
There are many countries in Europe and there are many prices of stamps. If you are talking about the cost of sending something to Europe, that will depend on where you are, what you are sending and where in Europe you are sending it to. You would need to go to your local post office to find out what it would cost.
98 cents is the 2010 rate for 1 oz letter to Europe from the US.
The cost of a letter being sent to Norway will be determined by where you are sending it from. The cost will also vary depending on the weight of the letter.
41cents
It is postage.
It is known as postage.
It depends where you are sending it from as well as the size and weight of the letter.
That will depend on where in the world you are sending it from and to which country in Europe you are sending it to, neither of which you have stated. Your local post office will have current prices for you.
postage
15,000 pounds
That depends on where you are sending the letter FROM.