I have to summarize the development of atomic theory. I think this question is talking about Dalton's atomic theory, is that right

Answer 1

Dalton's Atomic Theory was based on experimental evidence which lead to the laws of definite and multiple proportions. You may want to research that and other experimental evidence that supports the atomic theory. You will find a lot more about the development of the atomic theory from ancient times through the discovery of the parts of the atom here:
http://www.infoplease.com/ce6/sci/A0856763.html