The reaction of A, 2A+B2C is a third-order reaction of the form rA=kCA2CB with units of kilomoles of A reacted per L.h. The rate constant at 30C is k=85.28L2/mol2h. A reactor is charged with 250 moles of a gas containing 18.42mol%A,10.53mol%B, and 71.05mol% of an inert that does not take part in the reaction. The volume of the reactor is 25L. An isothermal operation at 30C is desired. How much time is required for a 90% conversion of A