Answer/Explanation:
In the study of history as an academic discipline, a primary source (also called original source or evidence) is an artifact, a document, diary, manuscript, autobiography, a recording, or other source of information that was created at the time under study. It serves as an original source of information about the topic. Similar definitions can be used in library science, and other areas of scholarship, although different fields have somewhat different definitions. In journalism, a primary source can be a person with direct knowledge of a situation, or a document written by such a person.
Athens and Sparta was the main combatants in the peloponnesian war.
Distribuídas: Aquellas que actúan en un área del cuerpo o de la estructura. Por ejemplo el peso propio de una viga. Puntuales: Cuando sólo actúan en un determinado punto. Por ejemplo la carga que colgamos en una polea. (I really Hope this helps)
