1. There are a number of problems with the code above.
The first is that it will not link, because of a missing
definition of m_wadgetCount. How do we fix that problem?

    a. wadget.h inside class definition:
        static int m_wadgetCount = 0;
    b. wadget.h: outside class definition:
        static int Wadget::m_wadgetCount = 0;
    c. wadget.cpp: top of file
        int Wadget::m_wadgetCount = 0;
    d. wadget.cpp: top of file
        static int Wadget::m_wadgetCount = 0;
    e. wadget.cpp member initialization list:
        Wadget::Wadget()
        :  m_d1(a), m_d2(b), m_wadgetCount(0)
            { m_wadgetCount ++; }

}


2. For the declaration of
      static int Wadget::wadgetCount()
   What does the static here mean?

   a. function must be defined in a .cpp file
   b. function can only be called on static objects
   c. function must be called with Wadget:: scope resolution
   d. function name has file scope
   e. function can only access static members


3. For the definition of
      static int Wadget::wadgetCount()
   What does the static here mean?
   a. function can only access static members
   b. function can only be called on static objects
   c. function must be called with Wadget:: scope resolution
   d. function name is exported to the linker
   e. function name is not exported to the linker


4. What can we say about the definition of Wadget::calculation()?

   a. d1 and d2 are not accessible from the static method
   b. missing a 'static' before the function definition
   c. there is nothing wrong with this.
   d. both a and b
   e. function name is not exported to the linker (error)