For a transmission line open circuit and short circuit impedances are 20 Ω and 5 Ω. Then characteristic

For a transmission line open circuit and short circuit impedances are 20 Ω and 5 Ω. Then characteristic impedance is: (1) 100 Ω (2) 50 Ω (3) 25 Ω (4) 10 Ω
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For a transmission line open circuit and short circuit impedances are 20 Ω and 5 Ω. Then characteristic impedance is: 10 Ω

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