please show the calculation

The data in Table 1 are derived from the degradation of a contaminant present in wastewater by a mixed culture of microorganisms. In an aeration tank, the process was continuously run. Table 1: Degradation of contaminant by microorganism If the contaminant (as substrate) concentration in the feed wastewater stream is reduced from 700mg/L to 500mg/L, how it affect the maximum growth rate of the microorganism? Will you suggest to reduce the substrate concentration