题目内容：
E-MONEY——MONEY OF FUTUREDescription: E-money, also called chip cards or (16)__________is a kind of (17)__________ for people to add (18)__________ to instead of coins and bills in their wallet. It is a (19)__________device like a computer disk or just a tiny processor.
Advantages:
(i) (20)
(ii) Safety
(iii) Cost
The card's value can be verified and .changed without going through a (21)__________ system such as a (22)__________ has to.
(16)__________
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