Level 29

You see a room which is 10x10m wide (0x0 to 9x9).
Every square has the exact temperature of 5°C. We apply continuously 74°C heat to the field 3x9
What is the temperature (rounded to whole numbers) in the field 2x8 after 42 iterations according to the Gauss-Seidel iteration

Field in the beginning

5555555555
5555555555
5555555555
5555555555
5555555555
5555555555
5555555555
5555555555
5555555555
5555555555

Field after 4 iterations (rounded after 4th iteration)

1112222211
1223333321
1234444331
2344444431
2344454432
2345555432
2357765532
2410161397532
28214025138531
3103310034136321

Temperature in field 2x8 after 42 iterations: