Question 1: Primitive social period. I can't. We must live a collective life.

The second question: Beijingers can already use natural fire. Using fire to make people eat cooked food is beneficial to digestion and nutrition is easier to absorb. The improvement of human nutrition level is more conducive to the development and evolution of the brain and the improvement of human labor and thinking ability, so the survival ability and survival rate of human beings are improved.

The third question: Man has learned to use artificial fire. Neanderthals learned to make fires. Neanderthals lived about 30 thousand years ago.

The second big question:

The first question: the legendary era (the end of primitive society) and the Xia Dynasty; The Xia Dynasty was founded around 2070 BC.

The second question: quoting ancient documents. You can also use the oral record method of interviewing the witnesses of the parties, the empirical method of cultural relics archaeology to ancient history, field archaeological excavation research and writing research reports, collecting folk historical legends and editing them. (referred to as collation oral method and archaeological research method)

The third question: The history of Xia Dynasty has been confirmed by archaeological excavations. The ruins of Erlitouxia Culture in Yanshi, Henan Province, excavated in 1950s, turned the legend of Xia Dynasty into a history that can be tested.

The third big question:

Choose C. Because Yuanmou Man is one of the earliest ancient human sites discovered in China. Before 1990, Yuanmou man was always considered as the location of "the earliest human fossil discovered so far" in China.

The above answers are professional and correct. Please feel free to use them. Please consider simplifying some answers.