First Order Kinetics: A worker in a hazardous waste recycling facility inhales and absorbs toulene at a rate of 22 micrograms / hour. He excretes 2 L per day containing 18 micrograms / liter toulene. If the blood volume of the individual is 5.6 L and the toulene is metabolized with a first order rate constant of 0.08 h^-1 what is the steady-state concentration of toluene in the individual's vascular system? Assume that storage is negligible.