A certain volatile substance evaporates from an open container into a room of volume $1000$ ft$3.$The evaporation rate is determined to be $100$ mg$/$min$.$ If the air in the room is assumed to be well mixed, how many ft$3/$min of fresh air must be supplied to ensure that the concentration of the volatile is maintained below its TLV of $100$ ppm$?$ The temperature is $77\backslash$deg F and the pressure is $1$ atm. Assume a volatile species molecular weight of $100.$ Under most circumstances the air in a

room cannot be assumed to be well mixed. How would poor mixing affect the quantity of air required?