Understanding under what conditions an enzyme achieves maximal velocity (Vmax) and the turnover number of an enzyme.

The enzyme carbonic anhydrase is found in erythrocytes, and has a molecular mass of approximately 30000 Da.  The hydration reaction catalyzed by this enzyme is reversible, and plays a role in the transport of CO2 from the tissues to the lungs.

H2O + CO2 <-> H2CO3

If 20 micrograms of pure enzyme catalyzes the hydration of 0.50 g of Co2 in 1 minute, at 37 degrees Celsius, under optimal conditions, what is the turnover number (kcat) for carbonic anhydrase?