How did the gupta rulers improve the economy of india

Agriculture remained the economic basis of society during the Gupta period. The Gupta rulers made it a point to increase agricultural production since land revenue was the primary source of income. Waste land was brought under cultivation. There were two principal harvests one for summer and the other for autumn.

School is almost over, good luck!!

these civilizations were located around fertile rivers, where they could produce an abundance of crops

is there even a question here? you seem to have the answer and there is no quote to look at.