For the system in the figure :

$($a$)$ If $L=120cm,$ what is the

pressure of air as inHg in

container $($A$)?($b$)$ Conversely,

if $P_A=33\mathrm{.}6$kPa, what is the

length $($L$).$

$($Ans$.P_A=9$inHg,$L=1\mathrm{.}38m)$