Circular flow models are used to show: A. how tax rates affect economic productivity.
B. how unemployment leads to economic problems.
C. how money moves through an economy.
D. how investments gain and lose value over time.

Basically, the model of Circular flow is an economic model used to show how money moves through an economy.

The circular flow model is an economic model that shows how money, goods and services moves between the sectors in an economic system.

Hence, the model of Circular flow is an economic model used to show how money moves through an economy.

Therefore, the Option C is correct.

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congress failed to remove johnson. but it did succeed in getting control of efforts to re-build the south following america's civil war. radical republicans wanted to punish the south for starting the war. they also wanted to be sure new governments in the southern states would support the republican party.