Find Vo in the circuit in Fig. E4.2 using(a) source exchange and (b) both Thévenin's a...

Find Vo in the circuit in Fig. E4.2 using

(a) source exchange and

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(b) both Thévenin's and Norton's theorems. When deriving the Norton equivalent circuit, break the network to the left of the 4-kΩ resistor. Why?

Figure E4.2