The first ounce will cost 44 cents. Each additional ounce, or fraction, is another 17 ounces. That would be 78 cents for that envelope at the start of 2011.
A 4-ounce large envelope currently costs $1.57.
I think you mean 9x12 envelope.
That depends on where you are sending it from (you country of origin) and to (the country of destination).
how many stamps for a 10.4 ounce envelope
how many stamps for a 3.4oz envelope
The amount of stamps needed for an envelope is determined by weight. Weigh your a4 envelope and you will know how much postage is needed.
Take your envelope to the Post Office and they will weight it, and give you your answer as the cost of mailing anything is done by weight.
That depends what denomination of stamps you place on the envelope.
That will depend on the value of the stamps and perhaps the dimensions of the envelope. If you have the right values, it would only be one, but it could be a dozen or so if you only have smaller values. Check your Post Office web site for the specific rate necessary.
As many as will fit. I have one envelope in my collection with 44 stamps on it! The sender used one cent stamps to mail it. Some people will overlap stamps to get more to fit, which is okay as long as the Post Office can plainly see that they are all there.
two
It depends on tne weight of the envelope not the size.