Using complete sentences, list three important characteristics of a republic

Republic is a form of government in which the power is given to elected individuals for a limited period and which represents the voters and governs according to the law. The head of state is directly or indirectly elected, or appointed in another way, and is usually called president. The opposite of republic is monarchy where the head of state, called king, inherits the throne by the simple fact of being born in a particular family.

The most important feature of the republic as a form of government is the electivity and changeability of the head of state, which in most cases excludes the hereditary or other non-elected way of transferring power.

yellow fever and other tropical diseases

it refers to race, i am pretty sure this was a popular term in nazi germany or something.