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virtual – adj. existing or occurring on computers or on the Internet
plausible – adj. possibly true : believable or realistic
transaction – n. a business deal : an occurrence in which goods, services, or money are passed from one person, account, etc., to another
puzzle – n. a question or problem that requires thought, skill, or cleverness to be answered or solved
reward – n. money or another kind of payment that is given or received for something that has been done or that is offered for something that might be done
cryptocurrency – n. a kind of virtual currency or money
digital – adj. relating to computer technology, especially the internet
