Hello, Jeanne and Scott, I noticed that explanation for the review question 10 contains error.
It is said
If the static modifier on line 4 was removed, then the class would compile and produce two files: Ostrich.class and Ostrich$OstrichWrangler.class.
It is wrong as I understand. If the static modifier on line 4 was removed then three files would be generated. One more for the inner interface.
Ostrich.class
Ostrich$OstrichWrangler.class
Ostrich$Wild.class