A euro is subdivided into 100 cents. Therefore you would receive 30 cents in change.
The euro was legally introduced in Greece in January 2002.
2008
2002
Banks, post offices, bureaux de change
Some countries do not use the Euro because they have their own currency and do not wish to change, or at least not for a while.
Currancy values change daily if not by the hour but 1 Euro is worth approx. $1.35 US
Hungary still uses the Forint. A date for it changing to the euro has not been set yet.
It is hard to give you the exact rate of change of euro in us dollar because foreign currency change everyday but I can give you what is the equivalent of 16 euro in us dollar for today. It is around 21 to 23 us dollars. See, for instance, this online converter: euro-to-dollar.net.
The exchange rates for the Euro can change over time but are fairly consistent overall. There are 1.28 US dollars, 1.39 Australian dollars to the Euro, and 128.6 Japanese Yen to the Euro.
Some supermarkets accept EURO bills, but not coins. Your change will be Danish Crowns (or Kroners) though.Not many outlets, if any at all, will accept EURO's.
Change it into dollars before you arrive.