多项选择题
When a computer does not recognize an internal modem， a technician should determine whether：（）
A.the modem is seated properly. B.the number being dialed is valid. C.there are resource conflicts. D.there is power to the modem. E.the modem speaker is enabled.
单项选择题 Whichofthefollowingwillhelpprotectanoperatingsystemfromvulnerability？（）
单项选择题 WhichofthefollowingRAIDconfigurationstakesadvantageofmirroring？（）
多项选择题 Whichofthefollowingshouldbeconsideredwhenupgradingmemory？（）
