Answer: Thee Multiplier Process
Explanation:
The Multiplier Effect is the change in income that results from a change in Expenditure.
Essentially it is the rise in income resulting from new injections of money.
Broadly speaking, injections can come from, Government Spending in the Economy, Investment by firms, Exports and the like.
Injections increase the flow of income as the text portrays as it translates to money going into someone else's hands which they use to do something that enables someone else to get paid and so on and so forth.
That is what happened in the text.
Mary got an injection from the US Government, this enabled a salesman to go on a date, which enables a Ballerino his rent .
An injection of extra income leads to more spending, which creates more income, and so on.
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