in 30 words or fewer explain the types of sources a historian would need to learn about what humans were doing in china 5000 years ago?

c.

worked constantly and gave many sincere speeches about the importance of independence

crop rotation kepy different plants in the soil instead of once constintly. when switching out plants you have different nutrients being absorbed at different speeds and different roots growing differently therfore the spoil and water flow have to adapt and carry fresh nutrients to carry the constant changes that were going on in the soil.