There was an increase demand for coal as an energy source yield democratic claims in some places and colonial domination in others because of democracy. Miners were in the better position to have voting rights, have higher wages and other benefits.
The reason is very simple - profit.
The rabbits were not worth much to the Europeans, but were to the Aztecs, but the cocoa beans for the Europeans were like gold. They were a very attractive exotic product from which unique and unseen things were made. In the European market the cocoa beans had enormous price, and the demand for it was very high especially from the aristocracy which loved it and didn't speared money for it.
This depends entirely on the research project in question. For instance, if you want to learn more about how the memorial was constructed, you could look at the history of its architecture, etc. Or if you want to know more about how it was conceived you should look at the debates surrounding it's creation.
<span>Mestizo (mixed Amerindian-Spanish - in local Spanish called Ladino)</span>