At \( 310 \, \text{K} \), the solubility of \( \mathrm{CaF_2} \) in water is \( 2.34 \times 10^{-3} \, \text{g}/100 \, \text{mL} \). The solubility product of \( \mathrm{CaF_2} \) is _____ \( \times 10^{-8} \, (\text{mol}/\text{L})^3 \). (Give molar mass : \( \mathrm{CaF_2} = 78 \, \text{g mol}^{-1} \) )
