21. Which of the following input devices reads barcode in a certain product? a. mouse b.barcode reader/ scanner c. keyboard d. digital camera 22. Which of the microcomputers below has the smallest in size? a. handheld/ PDA b. Personal Computer c. Macintosh d. Laptop/ Notebook 23. Which of the following devices store the entered information and programs for future use?? a. storage devices b.input devices c. output devices d. processing devices 24. There are two main parts of the system unit, the internal and external parts. Which of the options below protects the internal parts of the system unit? a. casing b. floppy disk c. power switch d. power supply 25. These are siols or holes where you plug cables and connectors. a. motherboard b. ports c. expansion slots d. video card 26. Which of the output devices below is like a television that displays data from your computer? a. plotters b. monitor c. printer d. speaker 27. It is usually pressed while you are working in a software application to stop the current activity back out a menu or return to the previous screen. a. enter b. spacebar c. escape d. shift 28. There are four main components of a microcomputer. Which among the four components store the entered information and programs for future use? a. storage devices b. input devices c. processing devices 29. Which of the following DOES NOT belong to the group? d. output device a. dot matrix b. inkjet c. laser d. CPU 30. Which of the following is the latest Windows line? a. Vista b. Windows 10 c. Windows 7 d. Windows 8​