Genitives & Attributive Modifiers

The average audience member may believe punctuation to be a minor part of a written work, but the copyeditor knows that a simple punctuation error can affect the author’s entire meaning. One of these finicky punctuation marks is the apostrophe. 

I was once asked whether it was correct to include the apostrophe in the following phrases: 

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And if the apostrophe should be included, should it be placed at the en...