Level 29

You see a room which is 10x10m wide (0x0 to 9x9).
Every square has the exact temperature of 39°C. We apply continuously 76°C heat to the field 7x4
What is the temperature (rounded to whole numbers) in the field 4x7 after 84 iterations according to the Gauss-Seidel iteration

Field in the beginning

39393939393939393939
39393939393939393939
39393939393939393939
39393939393939393939
39393939393939393939
39393939393939393939
39393939393939393939
39393939393939393939
39393939393939393939
39393939393939393939

Field after 4 iterations (rounded after 4th iteration)

5911121313131295
9151922232324231810
11192527293136403016
12222731344155724923
132329333849781507030
13233034384763805426
13232933374249524021
12202630323538372815
9152022242627241810
5810121313131295

Temperature in field 4x7 after 84 iterations: