**file1_surface1**
![file1_surface1](gifs/file1_surface1.gif)

**file2_surface2**
![file2_surface2](gifs/file2_surface2.gif)

**file3_iteration_methods**
![file3_iteration_methods](gifs/file3_iteration_methods.gif)

**file4_curvy_limits**
![file4_curvy_limits](gifs/file4_curvy_region.gif)