An open circular tank $5m$ in diameter and $5m$ in high contains benzene at $20C.$ The level of benzene in the tank is at $4m$ level as seen by a level indicator sight tube on the outside. Assume that the air in the tank is stagnant. Since the tank is open to atmosphere, the partial pressure of benzene at $20C$ is $100mmHg.$ The specific gravity of benzene is $0\mathrm{.}88.$ Molecular weight of benzene is $78\mathrm{.}11.$ Diffusivity of benzene in air at $20C$ and $1$atm is $0\mathrm{.}077c\frac{m^2}{s}.$

If benzene costs $50\frac{E}{L},$ what would be the loss of benzene from the tank in $\frac{}{?}$ day. Use to diffusivity equation