ANSWERS TO QUESTIONS Q1. AND Q49.

A1. The central processing unit.
A2. Three.
A3. Control section, internal storage section, and arithmetic-logic section.
A4. A telephone exchange.
A5. Transfer, arithmetic, logic, and control.
A6. Logic.
A7. Internal storage.
A8. Loading.
A9. Tiny doughnut-shaped rings made of ferrite iron.
A10. Hundreds of thousands of tiny electronic circuits etched on a silicon chip.
A11. Integrated circuits.
A12. All data in memory is lost when the power source is removed.
A13. Nonvolatile (magnetic core storage and bubble memory are examples).
A14. A very thin crystal made of semiconductor material.
A15. By passing a current through a control circuit imprinted on top of the crystal.
A16. The data is still present after being read.
A17. Read-only memory (ROM).
A18. Only the manufacturer.
A19. No.
A20. Read/write memory.
A21. By giving the computer the address of the location where the data is stored or is to be stored.
A22. Already programmed by the manufacturer or in a blank state.
A23. If a mistake is made and entered, it cannot be corrected or erased.
A24. Erasable programmable read-only memory.
A25. With a burst of ultra-violet light.
A26. Largely because of their direct access capabilities.

A27. In a number of invisible concentric circles called tracks.
A28. A disk address.
A29. By the bits per inch of track and the tracks per inch of surface.
A30. By cylinder or sector.
A31. Recording density.
A32. The usable recording (reading/writing) surface or usable storage area.
A33. The tracks in which the data is stored are assigned to channels that form circular bands around the drum.
A34. Sectors.
A35. To write data on or read data from a magnetic tape.
A36. The speed at which the tape is moved past the read/write head and the density of the recorded information.
A37. It gives us fast, immediate access to specific data without having to examine each and
every record from the beginning.
A38. A thin, flexible platter coated with magnetic material so characters can be recorded.
A39. 8 inch, 5 1/4 inch, and 3 1/2 inch.
A40. Printers.
A41. Daisy-wheel, dot-matrix, ink jet, and laser.
A42. To enter or input alphanumeric character codes.
A43. The display of alphanumeric data and graphics.
A44. Two.
A45. 525.
A46. Pixels or pels.
A47. The number of horizontal scan lines used.
A48. Reduce the depth of the crt display caused by the length of the tube.
A49. An external light source, called a backlight.