The concentration of gas phase PCBs in the air above Lake Salda was

measured to be $300$ picograms per cubic meter $($pg$/$m$3$

$).$ What is the partial

pressure $($in atm$)$ of PCBs$?$ Assume the temperature is $100$C$,$ the atmospheric

pressure is $1$ atm, and the average molecular weight of PCBs is $325$ g$/$mole$.$