Q3. Class Book (10 marks)
Book is also a specialized reference that has information about the publisher of this reference. It also has the number of pages as one of its attributes.
Book is a derived class of Reference.
It stores the publisher (type string or char) of this reference and the number of pages of this book (type int).
It also implements the member function getNumberOfPages(), which returns the number of pages of this reference. In the case of a Book reference, the number of pages is a single number. Therefore, the member function simply returns this number. It also implements functions related to the publisher.