For a transistor circuit, given Vcc, Ic, Vc, Ve, and beta, calculate Rc, Re, and Rb.

here are the solutions for Problems 10, 11, and 18 based on the provided diagrams.

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: Given the information provided in Fig. 4.123, determine:
Given: $V_{CC} = 12 \, \text{V}$, $I_C = 2 \, \text{mA}$, $V_C = 7.6 \, \text{V}$, $V_E = 2.4 \, \text{V}$, $\beta = 80$.
Assume $V_{BE} = 0.7 \, \text{V}$ for a silicon transistor.

a) $R_C$

Step 1: Calculate the voltage drop across $R_C$.

$$V_{R_C} = V_{CC} - V_C$$ $$V_{R_C} = 12 \, \text{V} - 7.6 \, \text{V} = 4.4 \, \text{V}$$

Step 2: Use Ohm's Law to find $R_C$.

$$R_C = \frac{V_{R_C}}{I_C}$$ $$R_C = \frac{4.4 \, \text{V}}{2 \times 10^{-3} \, \text{A}}$$ $$R_C = 2200 \, \Omega = 2.2 \, \text{k}\Omega$$

The collector resistor is $\boxed{\text{2.2 k}\Omega}$.

b) $R_E$

Step 1: Calculate the base current $I_B$.

$$I_B = \frac{I_C}{\beta}$$ $$I_B = \frac{2 \times 10^{-3} \, \text{A}}{80} = 25 \times 10^{-6} \, \text{A} = 25 \, \mu\text{A}$$

Step 2: Calculate the emitter current $I_E$.

$$I_E = I_C + I_B$$ $$I_E = (2 \times 10^{-3} \, \text{A}) + (25 \times 10^{-6} \, \text{A}) = 2.025 \times 10^{-3} \, \text{A} = 2.025 \, \text{mA}$$

Step 3: Use Ohm's Law to find $R_E$.

$$R_E = \frac{V_E}{I_E}$$ $$R_E = \frac{2.4 \, \text{V}}{2.025 \times 10^{-3} \, \text{A}}$$ $$R_E \approx 1185.19 \, \Omega = 1.185 \, \text{k}\Omega$$

The emitter resistor is $\boxed{\text{1.185 k}\Omega}$.

c) $R_B$

Step 1: Calculate the base voltage $V_B$.

$$V_B = V_E + V_{BE}$$ $$V_B = 2.4 \, \text{V} + 0.7 \, \text{V} = 3.1 \, \text{V}$$

Step 2: Calculate the voltage drop across $R_B$.

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