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battery - n. a device that is placed inside a machine (such as a clock, toy, or car) to supply it with electricity
transform - v. to change something completely usually in a good way
leading edge - n. being in the lead, out front
confident - adj. having a feeling or belief that you can do something well or succeed at something
range - n. a specified distance
lithium - n. a soft silver-white element that is the lightest metal known used in batteries for electronics
