Going to where? If you mean domestically within the US, then the US Postal Service rate would be $1.90 ... see the Related Links below for more info.
4
how many stamps for a 3.4oz envelope
As of 2016, a 2.5 ounce envelope it would cost 93 cents (one Forever stamp plus two extra ounces).
In a standard size envelope, as of June 2009, you need 75 cents in stamps to mail an envelope up to 1 ounce to Canada. You could use two 44 cent stamps (you would be paying too much) or you can buy 75 cents of stamps at a post office. You need an additional 25 cents worth of stamps for each additional ounce or fraction of an ounce. Letters over 3.5 ounces have different rates.
For a regular sized envelope up to 3.5 ounces, it is 98 cents for the first ounce and 84 cents for each additional ounce or fraction of an ounce.
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.
It depends on tne weight of the envelope not the size.
I think you mean 9x12 envelope.
5 as of January 18, 2013.
To send a standard letter from California to Georgia, you would need one first-class stamp. If the letter is heavier or larger than standard, additional postage may be required. It's always best to check with the postal service for the most accurate postage rate.
It only takes one for the first ounce. For additional weight, you will have to add additional stamps. Usually four sheets of paper in an envelope will need an extra stamp.
5 as of January 18, 2013.