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• S4.E1 ∙ American Steel: Built to Last
• S4.E2 ∙ Las Vegas Hotels
• S4.E3 ∙ Medical Imaging: The Voyage Inward
• S4.E4 ∙ Prosthetics
• S4.E5 ∙ Weather Predictions
• S4.E6 ∙ Captured Light
• S4.E7 ∙ Stealth Technology
• S4.E8 ∙ Pyramids: Majesty and Mystery
• S4.E9 ∙ Roller Coasters
• S4.E10 ∙ Observatories: Stonehenge to Space Telescopes
• S4.E11 ∙ The Great Wall of China