The Figure $($below$)$ presents the potentiometric map for a shallow sand aquifer. The hydraulic c

rigure $0\mathrm{.}10$

$($a$)$ What is the groundwater velocity $($Darcy$\text{'}$s velocity$)$ and seepage velocity across the plume $($use a scale bar to estimate the distance$)?$

Darcy's velocity $m\frac{m}{?}$ day Seepage velocity $=m\frac{m}{?}$ day

$($b$)$ Estimate how long $($years$)$ the source has been contaminating the aquifer. You may ignore the effect of dispersion, diffusion and adsorption $(t=\frac{L}{v_{\text{s}\text{e}\text{e}\text{p}\text{a}\text{g}\text{e}}})$

Time

years

$($c$)$ Estimate the volumetric flow rate per unit depth of plume in $\frac{m^3}{?}$ day $\frac{?}{m}$ across the plume.

$Q=$