4. For the parallel adder in Figure 6-69, determine the complete sum by analysis of the logical operation of the circuit. Verify your result by longhand addition of the two input numbers. Figure 6-69 Figure 6-70 1 0 A B Cin Cout Σε Σ A B Cin Σε Cout ΣΑ Σ 5. Repeat Problem 4 for the circuit and input conditions in Figure 6-70. Ο Ο A B Cin Cout Σ 1 0 ΣΑ A B Cin| Cout Σ A B Cin Cout Σ A B C Σ; Cout Σ 0 1 Σ A B Cin Cout Σ Στ A B Cin Cout Σ

28. For each circuit in Figure 6-83, determine the Thevenin equivalent as seen from terminals A and B. 2.5 V (a) R₁ 100 (2 R3 www 47 Ω FIGURE 6-83 R₁ 22 (2 R₂ 78 Ω A B R₁ (b) R₁ 100 (2 R₁ B 3 V HOF ✓ R₂ 270 Ω =1.5 V (c) R₁ 100 ΚΩ R₂ 56 ΚΩ B RL

53. Find RT in Figure 5-87. ➤FIGURE 5-87 R₂ 12 V www = 5,6 ΜΩ R₁ = 4.8 V Ry www P = 21.5 μW