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阅读下面的短文，文章中有5处空白，文章后有6组文字，请根据文章的内容选择5组文字，将其分别放回文章原有位置，以恢复文章原貌。
The paperless office is not a dream, it is a joke. Today more gadgets(小器具) are devoted to spattering more paper with more ink than ever before. At last a Japanese manufacturer of office equipment, Ricoh, is trying to reverse the trend. (46) The age of the recycling non-violent shredder may be about to dawn.
(47) The new machine sprays on a chemical to loosen the toner’s grip, applies a little heat and then uses a sticky roller to peel the toner(增色剂) off,
Using this technology, a single sheet of paper can be recycled 10 or 20 times, depending on its durability. And as well as eliminating bins full of waste paper, the machine could silence ’the shredder. (48) The result would not fool the experts in a forensic(法医) laboratory, but is might well suffice for low-level security.
(49) The prototype cleans only three pages a minute. Ricoh has yet to show it can make erasing old paper cheaper than buying new. And only the toner is removed: the ma chine cannot wipe out marks made by dot matrix printer or thermal-paper fax machines. (50) This means that text or figures produced with a laser printer could be altered, but letterheads and signatures on the same piece of paper would be left intact.
A. More work is required.
B. Anyone concerned about secrecy could erase his message rather than reduce it to tangles of shredded paper.
C. He has developed a machine that takes in printed paper and spits out clean white sheets.
D. The new machine can tear paper sheets into pieces.
E. Pen strokes and impressions made with ordinary printing presses are also immune.
F. Most photocopiers, laser printers and plain-paper fax machines make their marks with toner, which is melted on to the surface of the paper.