The (71) is a pointing device that controls the pointer on the screen.
A. keyboard
B. mouse
C. scanner
D. printer
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(72) acts as the manager of computer resources.
Application
B. Operating system
C. I/O
Data
A basic feature of all (73) is the capably to locate records in the file quickly.
APP
B. OS
CAD
DBMS
Each Web site has its own unique address known as a (74)
A. URL(Uniform Resource Locator)
B. IP(Intemet Protocol)
C. HTML(Hyper Text Markup Language)
D. WWW(World Wide Web)
Make (75) copies of important files to protect your information.
A. save
B. back-up
C. support
D. ready
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