Yes, most U.S. bills from 1996 on, including the $20 note, have watermarks.
Yes, but only on modern bills. When looking at the front side of the bill, the watermark is to the right, visible when held to light. It shows President Jackson's portrait.
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There are a number of counterfeit foiling technologies. One is the thread that runs through the bill, stating is USA $20. There is also a watermark that does not photocopy well.
No, there's only a single watermark on current US bills $5 and above. $1 and $2 bills don't have watermarks.
Andrew Jackson is on the 20 dollar bill
Queen Elizabeth II of the United Kingdom is on the New Zealand twenty dollar note. The first edition of the note also featured a watermark with a portrait of Captain James Cook.
As of 06/2014 it has no added value, even in uncirculated condition.
The White House is on the twenty dollar bill. ($20)
No there is no such thing as a zero dollar bill. And if you thought there is such thing as a 20 dollar bill, there is such a thing!
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