Problem 1  
Jacobi iteration requires 798 iterations
For a better effect, I have rescaled the z-axis by 10

 
Gauss-Seidel iteration requires 690 iterations


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Problem 2
 
When omega = 1.95,  rouO = 0.94.


Problem 3
SOR method with omega = 1.95; Requires 100 iterations.

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