"Your muscles get cold and are instantly paralyzed by the hyperventilation, and you can become very weak, " says Dr. Thomas Traill, a cardiologist and professor of medicine at Johns Hopkins University School of Medicine.

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"He's become a very weak mayor, " said Rahaman Muhammad, president of the Newark labor union, SEIU Local 617, a former supporter who is now an outspoken critic.

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When you have done a few presentations, you will become very familiar with the areas in your business that are weak.

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