An enzyme catalyzes the reaction a → b. the initial rate of reaction was measured as a function of the concentration of a. the following data were obtained: [a], micromolar v0, nmoles/min 0.05 0.08 0.1 0.16 0.5 0.79 1 1.6 5 7.3 10 13 50 40 100 53 500 73 1,000 76 5,000 79 10,000 80 20,000 80