Barack Obama is an exception, and even he satisfies two of three characteristics: rich and male.

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In addition, all feature a specially designed Acoustic Optimizer that ensures dynamic sound and deep rich bass response, with optimum acoustical characteristics achieved by adjusting the sound pressure balance in front of and behind the diaphragm.

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This is the fact that the French tend to eat fatty diets rich in red meat but to have the survival characteristics of those whose diets are lean and vegetarian.

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The early evolution of dinosaurs is difficult to unpick, as a rich variety of reptiles were proliferating at the time - and some may even have independently evolved characteristics that are associated with dinosaurs.

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