Which dynasty was known for adding blue cobalt dye to porcelain that helped it reach its peak in China?

Charlemagne or Charles I was the grandson of

The Qin dynasty first started the Great Wall project around 200 BCE. Which best describes it around this time?

What were the differences between peasants and serfs?

At what age did a knight's training begin?

This invention of medieval China was done by accident as Taoists sought a cure for everlasting life:

Medieval Bibles were...

Which Renaissance leader invented a clock that could tell not only the time of day, but also the phase of the moon?

What caused the plague (Black Death/Bubonic Plague)? Options: Eating infected food, Spreading of a bacteria called Yersinia, Spreading of a virus called Pelagius, All the above

The final emperor of China was ...