We worked with a typical condition from the NASA Langley $20-$inch Mach $6$ Wind Tunnel

Facility in homework $1.$ That condition has a freestream condition of Mach $6,$ pressure of

$2,650Pa,$ and temperature of $50$ K $($we will call this Condition A$).$ Blowdown wind tunnels

like this typically generate airflow by isentropically expanding a large reservoir of gas that

contains the desired total pressure and total temperature of the freestream air. A common

practice with high$-$speed wind tunnels is to match the Mach number and Reynolds number

of flight while keeping the test gas as cold as possible $($in this case $50$ K $).$ The above test

condition is considered a simulation of flight at Mach $6$ at an altitude of $15$ km $,$ which has a

static pressure of $12,112Pa$ and a static temperature of $217$ K $($we will call this Condition

B$).$ Assume that air is a calorically perfect gas and compute the following: