4. The reaction BC is carried out in a laboratory reactor. The concentration of B should vary with time as follows: CB=CB0exp(0.314t) where CB0=1.4lbmoles/ft3 is initial concentration, 0.314 is reaction constant (min1) Convert the formula with the calculated constants included to an expression for the molarity of B in the reaction mixture in terms of (seconds) and calculate the molarity at t=50s