a metered postcard is a postcard that already has the stamp made into the the postcard. there is no need to put an adhesive stamp on it.
Yes, you can use a Forever stamp on a postcard, but it's overpaying for postage.
cost of airmail stamp on a postcard from usa to south Africa?
Probably the amount of a stamp, or less, depending on how heavy the postcard is. But A stamp would work just fine.
A stamp . . . as on an envelope or postcard.
You will need a postcard stamp. They currently cost $0.29.
No
over the bar code
It depends on where you are sending it from.
99c
1 cent
32 cents