A completely mixed activated sludge system with a volume of $10000m^3$ treating $17500\frac{m^3}{d}$ domestic wastewater is operated at an SRT of $15$ days and an MLSS concentration of $3000m\frac{g}{L}.$ How much sludge $($kg$/$day$)$ wasting is necessary from the system?

a$.2000k\frac{g}{d}$

b$.5000k\frac{g}{d}$

c$.3000k\frac{g}{d}$

d$.4000k\frac{g}{d}$