Help with exercise

Hello everyone! I should transfer in " dynare " th model containing in the file “model_project.pdf” and perform the exercise contained in the last page of the other pdf .
I attach the mod file . Can someone please help me?
progetto11.mod (1.06 KB)
exercise.pdf (88.7 KB)
model_project.pdf (94.3 KB)

Check your model. If you define pip as a parameter, your equation

is not linear anymore. Moreover, using a leaded parameter makes no sense.

resid(1); before steady to see the problematic equations.