In the casting of steel under certain mold conditions, the mold constant in Chvorinov's rule is know to be 4.0 min/cm2 , based on previous experience. The casting is a flat plate whose length = 30cm, width = 10cm, and thickness = 20cm. Determine how long it will take for the casting to solidify. If solving for the total solidification time in the previouse problem and using an exponet value of 1.9 in Chvorinov's rule instead of 2.0, what adjustment must be made in the units of the mold constant?