8) How many gates, inicluding inverters, are required to implenent the equation, X-A AB AB 18) after it is simplified using Boolean algebra? C) 3 D) 4 B) 2 19) The NAND gate is referred to as a "universal" gate, because it C) can be used to build all the other types of gates A) 1 19) A) is used in all the countries of the world B) can be found in almost all digital circuits D) was the first gate to be integrated Figure 5-3 20) Which circuit in Figure 5-3 represents the NAND implementation of a NOR gate? 20) A) Figure (A) B) Figurel B). C) Figure (C). D) Figure (D). 21) Which circuit in Figure 5-3 represents the NAND implementation of an AND-OR function? A) Figure (A) B) Figure (B). C) Figure (C) 21) D) Figure (D). 22) Which circuit in Figure 5-3 represents the NAND implementation of an inverter? A) Figure (A) B) Figure (B). C) Figure (C). 22) D) Figure (D)