9. Name the four basic logic gates. 10. What are the two universal gates described in this chapter? Why are these universal gates important? 11. Describe the basic construction of a digital logic chip 12. Describe the operation of a ripple-carry adder. Why are ripple-carry adders not used in most computers today? 13. What are the three methods we can use to express the logical behavior of Boolean functions? 14. What are the necessary steps one must take when designing a logic circuit from a description of the problem? 15. What is the difference between a half-adder and a full adder? 16. What do we call a circuit that takes several inputs and their respective values to select one specific output line? Name one important application for these devices. 17. What kind of circuit selects binary information from one of many input lines and directs it to a single output line? 18. How are sequential circuits different from combinational circuits? 19. What is the basic element of a sequential circuit? 20. What do we mean when we say that a sequential circuit is edge triggered rather than level triggered? 21. In the context of digital circuits, what is feedback? 22. How is a JK flip-flop related to an SR flip-flop? 23. Why are JK flip-flops often preferred to SR flip-flops? 24. Which flip-flop gives a true representation of computer memory? 25. How is a Mealy machine different from a Moore machine? 26. What does an algorithmic state machine offer that is not provided by either a Moore or a Mealy machine