What event influenced the rise of medieval feudalism in the 9th century ? a) the death of the Emperor Charlemagne
b) the riots under the Emperor Justinian
c) the Crusaders sack of Constantinople
d) the meeting of the Estates General

a) the death of the Emperor Charlemagne

Explanation:

Emperor Charlemagne or Charles the Great, was king of the Franks in 768-814 in which he later became the emperor of the West in 800-814. He founded the Holy Roman Empire, stimulated European economic and political life, etc.

After his death, his empire was invaded by Vikings which led to the local nobles to took over the duties of protecting their properties. This the did, through the raising of local armies. As this power passed to the local lords rather than the kings appointed by the emperor, it gave rise to feudalism.

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.

keeping a cash reserve because cash flow is the the movement of money through a company and if it just sits there, it wont the movement