Unit Operations in Dairy and Food Engineering

An ultrafiltration membrane unit processes sweet whey ($6.0\%$ total solids) to concentrate proteins. The volumetric rejection coefficient of whey protein is $R = 0.98$. If the feed protein concentration is $C_f = 8.0\text{ g/L}$, the protein concentration in the permeate $C_p = C_f (1 - R)$ in $\text{g/L}$ is ________ (round off to 2 decimal places).