Question $1(20$ Marks$)$

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A telephone line has the following parameters:

R $=40$ W m$-1,$ G $=400$ mS m$-1,$ L $=0\mathrm{.}2$ mH m$-1,$ C $=0\mathrm{.}5$ nF m$-1.$

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$$ i$.$ If the line operates at $10$ MHz$,$ calculate the characteristic impedance Zo and velocity u$.$

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$(15$ marks$)$

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$$ii$.$ Determine how far the signal needs to travel $($in meters$)$ I in the line, before the voltage drops by $30$ dB$.$

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$(5$ marks$)$

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