Who proposed the plum pudding model and what does it say about the structure of the atom

J. J. Thomson

Explanation:

First proposed by J. J. Thomson  in 1904 soon after the discovery of the electron, but before the discovery of the atomic nucleus, the model tried to explain two properties of atoms then known: that electrons are negatively-charged particles and that atoms have no net electric charge.

pie chart because it is in percents ( % )

10 years is the answer