A $2-$stage reverse osmosis $($RO$)$ membrane system for brackish water desalination is shown in Figure O$3.$ The feed to the system has a flowrate of $80m^{2}id$ and total dissolved sold $($TDS$)$ contert of $1500mg$ L$.$ Both stages have the same recovery and the system recovery is $64\%.$ Assume the concentration polarization factor is $1\mathrm{.}2.$ Al the membranes have intrinic rejection of $99\%.$ All the permeates from Stage$-1$ and Stage$-2$ are blended to make the final product water. The temperature is $25C.$

$c_{t,}.$ The temperature $is25C.y=\frac{{}_e}{G_4}=0\mathrm{.}64$

far $1*2$

$($a$)$ Determine the TDS content of final product water. Does the final product water meat the requirement of $40m\frac{g}{?}.?$ State all assumptions made.