How many stamps needed for mailing an 8.5 x 11 envelope without about 15 sheets in it in the US?

Using a plain white paper envelope and 20 pound copy paper. My scale says the envelope + 15 sheets = 3.1 ounces. That would require four stamps You can send 20 sheets for the same price but 21 sheets will cost you another stamp.Be aware that paper is fairly standard in weight but not all envelopes are the same weight.

A "rule of thumb" I have used successfully for many years is that 5 sheets and a number ten envelope weighs exactly one ounce.

Unfortunately, I don't have that answer. Here are some U.S. Postal Service|US Postal sites that might help.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.