The enzyme glucose oxidase (GOx) catalyzes the conversion of glucose to gluconic acid in the presence of the cofactor FAD and oxygen. Consider a batch reactor that contains 0.3 mM of dissolved GOx and 100 mM of glucose at time equal zero. There are no inhibitors present. The initial rate of production of gluconic acid is 2 mM/min. After 5 minutes of reaction, the glucose concentration has dropped to 90 mM. After 50 minutes of reaction, the glucose concentration has dropped to 4 mM, and the rate of production of gluconic acid is 1 mM/min. Estimate the Michaelis constant for this enzymatic reaction? Justify your answer.