Soil-Water-Plant Relationship

In a field infiltration trial fitted to Philip's two-term equation $I = S t^{0.5} + A t$, the sorptivity parameter is $S = 2.0\text{ cm}\cdot\text{h}^{-0.5}$ and transmissivity factor is $A = 0.50\text{ cm/h}$. The cumulative infiltration depth $I$ after elapsed time $t = 4.0\text{ hours}$ in $\text{cm}$ is ________ (answer in integer).