3000. Kilo means thousand. Kilogram is 1000 grams, kilometre is 1000 metres. Kilowatt is 1000 watts etc.
How many cups depends on what substance you are measuring. Cups is a measure of volume, or the space taken up by the substance. Grams, however, is a measure of mass, basically how heavy the substance...
3 ounces = 85.0485694 grams
a kilogram is 1000 grams
3 grams = 0.105821886 ouncesSee Sources and related links for converter.