6. Find δ using source exchange. 7. Use Thevenin's theorem to find Z. 8. Use Norton’s theorem to find Z′.
a) The delta connection is used for impedance measurement, and Thevenin's and Norton's theorems are not applicable.
b) Source exchange is used for current calculation, and Thevenin's and Norton's theorems are applicable to voltage sources only.
c) Source exchange is used for voltage calculation, and Thevenin's and Norton's theorems are applicable to both voltage and current sources.
d) Thevenin's and Norton's theorems are both used for impedance calculation, and source exchange is not applicable.