Dear experts consider the situation below. Object is located in the sphere as shown below. And observer is on opposite side. In such cases please tell me how to decide mu1 and mu2.?. Is the object considered to be in air or in glass

Dear student
In the figure provided the object is inside a glass sphere that is filled with air. But as we are observing it outside of the sphere we consider it inside a glass sphere. hence we take u= 1.5 for the object.
I hope it will help you!
Regards