During a fed$-$batch bioreactor run $1$M NaOH $($~$1600$ mM$)$ is used to control the

pH$.$ In addition, a feed solution with an osmolarity of $1500$ mOsm is used for fed$-$

batch operation. The starting cell culture medium has an osmolarity of $320$

mOsm. If the total base addition was $30$ mL$/$L of culture and if the total feed was

$300$ mL$/$L of the culture, estimate the final osmolarity.