With the two$-$box model in Python we discussed in class, revise the code to add transport and depositions for both boxes, shown as the blue color below. Assume wind and deposition velocities $(u1,u2,$ vd$1$ and $vd2,$ in $\frac{m}{m}in)$ to be constants can be decided by users.

a$)$ Attach your code for the model $($only the model part, not those you make plots etc.$)$

b$)$ Assume your own inputs to run the model and plot a figure for $C_1$ and $C_2$ with time $($like the example shown in class$).$ Attach the figure. Indicate the parameters that you use to run the model as below. You need to choose a timestep to make your numerical solution stable.

Source $($S$1$ and S$2)$: $,$ Wind speed $($u$1$ and $u2$ Timestep $($dt$)$:

Deposition velocity $($vd$1$ and $vd2)$: $\frac{m}{m}in,$ Initial condition for $C_1$ and $C_2$ :