Answer:
a) The Tripartite Struggle for control of northern India took place in the ninth century, among the Pratihara Empire, the Pala Empire and the Rashtrakuta Empire and the struggle between the Pratihara Empire and the Rashtrakuta Empire had begun earlier than the struggle over Kannauj
b) The form of the Chola government was hereditary monarchy. The rule of primogeniture generally prevailed. The king generally appointed his Yuvaraja (heir) during his reign
c) Amoghavarsha was a Rashtrakuta emperor, the greatest ruler of the Rashtrakuta dynasty, and one of the great emperors of India. His reign of 64 years is one of the longest precisely dated monarchical reigns on record.
d) The revenue of the Chola kingdom came from the taxes on land and the produce of the land, and tax on trade and the part of the revenue was kept for the king and the rest were used on public works, such as the building of roads and tanks, on salaries of officials, on paying for the upkeep of the army
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