()isacopyofafileforuseintheeventoffailureorlossoftheoriginal.
A. secondstorage
B. buffer(缓存)
C. backup(备份)
D. database(数据库)
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When you move the mouse pointer to a ( ), the pointer's shape usually changes to a pointing hand.
A. hyperlink(超链接)
B. selected text(已选的文本)
C. selected graphic(已选的图形)
D. web page(网页)
Web pages are viewed with( )。
A. application
B. browser(浏览器)
C. OS(操作系统)
DBMS(数据库管理系统)
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