Why do you think the Byzantines and Persians were surprised by the strength of the Arab Muslims?

Why did the fighting go on after the armistice was signed

On a production possibility curve, data points that fall outside of the curve represent an inefficient allocation of resources. a balanced allocation of resources. ideal production. a currently unattainable production.

High schoolhow did gutenberg's printing press contribute to the growth of learning and literacy (especially bible reading) in europe?