Walk onstage carrying an ordinary briefcase and set it down on the table.
When you open it up, remove a basketball or other large item that cannot possibly fit in the briefcase.

Walk onstage carrying an ordinary briefcase and set it down on the table.
When you open it up, remove a basketball or other large item that cannot possibly fit in the briefcase.

Walk onstage carrying an ordinary briefcase and set it down on the table.
When you open it up, remove a basketball or other large item that cannot possibly fit in the briefcase.

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