What's the postage on this letter to Mexico please?
How would you like to send it?
By registered airmail.
$0.90 please. And please write down the postal code in the mailing address, anything else?
Yes, I'd like 6 postcards and 1,050 cent stamps please.
All right, here you are.
And this packages for London. Will you wait for me?
Yes, of course. This package is 10 grams overweight, you'll have to pay $0.50 extra for the overweight.