Level 29

You see a room which is 10x10m wide (0x0 to 9x9).
Every square has the exact temperature of 23°C. We apply continuously 129°C heat to the field 5x6
What is the temperature (rounded to whole numbers) in the field 4x9 after 70 iterations according to the Gauss-Seidel iteration

Field in the beginning

23232323232323232323
23232323232323232323
23232323232323232323
23232323232323232323
23232323232323232323
23232323232323232323
23232323232323232323
23232323232323232323
23232323232323232323
23232323232323232323

Field after 4 iterations (rounded after 4th iteration)

3577888753
5911131314131295
711141617181816126
713161821252421158
8131722334439291910
8141932599467422512
814224393223101532913
7132036649970442612
510152437494130189
358121721191494

Temperature in field 4x9 after 70 iterations: