Which of the following printers requires a specialized paper in order to operate?（）

单项选择题Which of the following is the correct connector for an internal floppy drive?（）

A. 50-pin SCSI
B. 40-pin ribbon
C. 34-pin ribbon
D. 4-pin SATA

单项选择题Which of the following ports is the default for HTTP?（）

A.21
B.25
C.80
D.110

单项选择题Which of the following keys is pressed to enter the Windows boot options after POST?（）

A.F1
B.F8
C.F10
D.F12

单项选择题A networking device that sends packets to all connections is a:（）

A. gateway.
B. hub.
C. switch.
D. router.

单项选择题A technician is servicing a customer’s color laser printer and notices excess toner in the printer.Which of the following tools would BEST assist the technician in removing the excess toner?（）

A. Damp towel
B. Compressed air
C. Alcohol wipe
D. Computer vacuum