Final answer:
The question explores the inheritance hierarchy in object-oriented programming, specifically concerning a package of exercises that can be linked to an online service providing further practice and skill testing.
Step-by-step explanation:
The student's question relates to the inheritance hierarchy in object-oriented programming. In object-oriented programming, inheritance allows new classes to adopt properties and methods from existing classes. This concept forms a hierarchy because each new subclass can itself become a parent class for further subclasses.
The exercises package mentioned could refer to a collection of coding exercises that demonstrate these principles. These exercises might be linked to an online service that offers additional practice, complete solutions, and skill testing across different platforms, such as mobile and PC.
The idea behind an inheritance hierarchy is to promote code reuse and organization, allowing more complex behaviors to be built upon simpler and more widely applicable ones. If a book includes such exercises, they typically aim to help students better understand how classes are related through inheritance, which is fundamental to building well-structured object-oriented applications.