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three-dimensional - adj. having or seeming to have length, width, and depth
hesitant - adj. slow to act or speak especially because you are nervous or unsure about what to do
serial number - n. a number that is put on a product and that is used to identify it
undetectable - adj. impossible to discover or notice
firearm - n. a small gun
metal detector - n. a device that can tell if metal is present
absurdity - n. extremely silly, foolish, or unreasonable idea
whim - n. a sudden wish, desire or decision
