Answer:
4) to reduce greenhouse gases
"Cordilleras" <span>are parallel sets of mountain ranges within the Andes Mountains. A cordillera is a chain of mountain ranges - and it is an extensive chain. The term itself originates from Spanish that has the same meaning. It is applied to different ranges that includes the Andes of South America but seldom on other mountain ranges in the ridge.</span>
The opinions and prejudice of an author in writing.
I believe that those two elements greatly affect bias in history because we can never be 100% sure of everything that (may have) happened in history (especially farther in the past), so opinion can affect a historian's writings. Also, everyone is prone to some sort of prejudice, so this can also affect history.