$($i$)$ Write the Finite Difference Approximation $($FDA$)$ of the temperature transport equation in the case of pure convection $\frac{\text{d}\text{e}\text{l}}{\text{d}\text{e}\text{l}\text{t}}+u\frac{\text{d}\text{e}\text{l}}{\text{d}\text{e}\text{l}\text{x}}=0$ adopting an explicit formulation and using forward differences in time and central differences in space for the advection term.