Which of the following states the Gravity model correctly?
1
\( \mathrm{T}_{i j}=\mathrm{A}+\mathrm{Y}_i+\frac{\mathrm{Y}_i}{\mathrm{D}_{i j}} \\\)
2
\( \mathrm{T}_{i j}=\mathrm{A} \times \mathrm{Y}_i \times \frac{\mathrm{D}_{i j}}{\mathrm{Y}_j} \\\)
3
\( \mathrm{~T}_{i j}=\mathrm{A} \times \mathrm{Y}_i \times \frac{\mathrm{Y}_i}{\mathrm{D}_{i j}} \)
4
\( \mathrm{~T}_{i j}=\mathrm{A} \times \mathrm{Y}_i \times \frac{\left|\mathrm{Y}_j\right|}{\mathrm{D}_{i j}} \)