Each box contains 10 items. Box 1
Net mass A = 10 grams
Box 2
Net mass B = 5 grams
Box 3
Each made of 1 A and 1 B

Mass box A = 10 grams; Mass box B = 5 grams; Mass box C-made of one A and one B
Mass ratio A/B =

Which of the following observations indicates that there is a small, dense, positively charged part in the center of an atom? some uncharged particles are scattered by a gold foil. all uncharged particles are attracted towards a gold foil. all positively charged particles pass straight through a gold foil. some positively charged particles bounce back from a gold foil.