$3)($a$)$ An amplifier has a $\backslash ($ T$\_\{$e$\}\backslash )$ of $170$ K a bandwidth$($B$)$ of $1$ GHz and a gain of $20$ dB $.$ Determine the noise floor $($in dBm $)$ of the amplifier.

$[3][$CO$01][$BTL $1]$

$($b$)$ A lossy transmission line has a noise figure of $1$ dB at room temperature. Calculate the noise figure of the line at $\backslash (0^\{\backslash$circ$\}\backslash$mathrm$\{$K$\}\backslash ).$

$[3][$CO$01][$BTL $2]$

$($c$)$ A $\backslash (10-12\backslash$mathrm$\{$GHz$\}\backslash )$ amplifier has a gain $20$ dB ; noise figure $3\mathrm{.}5$ dB and an output power $10$ dBm at its $1$ dB compression point. What is the dynamic range of amplifiers?

$[6][$CO$01][$BTL $2]$