In your own words, explain how dalton's theory of atoms in the development of the modern atomic theory.

Well, he introduced the theory that said that elements  are differed due to the mass of their atoms.
This theory is used to make the periodic table that we can see today. I think that is enough reason how Dalton helped the development of modern atomic theory

hope this helps

The exposition introduces Manuel as a clever boy.

Explanation:

This excerpt is an exposition as it sets the stage for the things to follow. Details about the theme, the setting, the characters and some things that are taking place are told in order to develop the following situations. In this case, we know that the story is set in a kingdom, and that one of the principal characters is Manuel as he is going to make the story move forward by taking action. He will make things change for good or for bad. In this exposition Manuel is described as a smart or clever boy, this is the reason he feels capable of solving a riddle to win money. He is so selfconfident that he thinks he can actually outsmart the princess.

By reading these we already know what actions are going to take place and the intentions of the character, we don't know the result of these actions yet.