Problem $6$: Following figure shows an experiment for flow through the layered soil. Water level in the piezometric tube inserted at the junction of two soils rose to $10cm$ above point $C$ as shown. Hydraulic conductivity of the soil $1$ was found to be$,k_1=8c\frac{m}{?}$ day. Find the value hydraulic conductivity of the second soil layer $(k_2)$ in $c\frac{m}{?}$ day

A$)4\mathrm{.}0c\frac{m}{?}$ day

B$)2\mathrm{.}6c\frac{m}{?}$ day

C$)1\mathrm{.}6c\frac{m}{?}$ day

D$)8\mathrm{.}0c\frac{m}{?}$ day