The answer is: 3 Drops.
After several years of marriage, the 'thrill' or 'passion' that make a person think they fell in love with one another tend to start to diminish.
This made them tend to reduce the effort that each couple made to court/impress each other, which lead to the drop in satisfaction.
A good example of a secondary source document useful in the study of history would be a textbook, because it provides basic information even though it wasn't an actual document from the historical time period.
The correct answer to this question, should be:
B.) You are exempt from your city's zoning laws.
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