The solubility of \( \mathrm{CdSO_4} \) in water is \( 8.0 \times 10^{-4} \, \mathrm{mol \, L^{-1}} \). Its solubility in \( 0.01 \, \mathrm{M} \, \mathrm{H_2SO_4} \) solution is _____ \( \times 10^{-6} \, \mathrm{mol \, L^{-1}} \). (Assume that solubility is much less than \( 0.01 \, \mathrm{M} \))