How does a tennis ball achieve its signature bounce? Can you really get lead poisoning from a number two pencil? If a hot dog isn�t made from dog meat, what�s actually inside one of America�s favorite foods? And just how does a firework burst into multiple colors and patterns at exactly the right time? Find out the answers to these questions and more in this episode of �Engineered.� Take a fast-paced and fact-filled adventure into the world of product design, manufacturing and testing as we go behind-the-scenes to find out how people and machines create some of life�s most fascinating things.