In the 900s, anglo-saxon kingdoms united to form the kingdom of

England

Explanation: In the 900s, Anglo-Saxon kingdoms united to form the Kingdom of England. The Anglo-Saxons were Germanic people. They migrated to the southe of Great Britain and seven kingdoms were formed by the Anglo-Saxons. In the 900s the kingdoms unified into one kingdom that was known as the kingdom of England.

an effect of the steamboat's popularity was that people began building canals in the united states and europe. this was done to find another way to transport goods across the country and in that time, transportation using the river was very slow and dangerous. it depended entirely on manpower and the current of the river. that all changed in the late 1700's when steamboats were introduced. they soon revolutionized travel and trade through the river and dominated the waterways. eventually, other means of transportation took over from the steamboats, but there was a time that they the united states to expand to the west.

answer: (fluidity)is the correct answer.

explanation: because of this characteristic, success on the battlefield depends in large part on the ability to adapt to proactively change events to our advantage as well as to react quickly to constantly changing conditions