$9\mathrm{.}21$ Develop a plot of ${}_z,u$ and ${}_z^{\text{'}}$ versus depth for the soil profile in Figure $9\mathrm{.}11.$ Consider depths from $0$ to $10m,$ assume hydrostatic conditions are present, and assume $u=0$ above the groundwater table. Plot depth, $z,$ on the vertical axis, with zero at the top and increasing downward. This method of plotting the data is easier to visualize, because depth on the plot is comparable to depth in a cross$-$section.