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Take a look around the room you’re in. An electric light probably illuminates the space, and you may be looking at a chair or a desk.
Perhaps there’s a laptop or tablet in view, too. If you’re in the kitchen, you may see a box of juice on the counter. If the TV is on, you might see images and hear voices or music. These are things most of us take for granted, but every single one of them is the solution to a problem and the end product of the engineering process.