You will be creating a program that implements the observer design pattern. this design pattern is utilized in almost all gui systems and is the basis for distributed event handling. the goal of the program is to create a class (the subject class for this assignment) that has a private variable (address) that can be modified via a standard mutator function (setaddress). this class has additional member functions that allow other classes (the observers) to register and deregister themselves with the subject. if observers are registered with the subject, they will receive notifications (via a callback function) if the subject’s address ever changes.

Consider the following code snippet: #ifndef cashregister_h#define cashregister_hconst double max_balance = 6000000.0; class cashregister{public: cashregister(); cashregister(double new_balance); void set_balance(double new_balance); double get_balance() const; private: double balance[12]; }; double get_monthly_balance(cashregister bk, int month); #endifwhich of the following is correct? a)the header file is correct as given.b)the definition of max_balance should be removed since header files should not contain constants.c)the definition of cashregister should be removed since header files should not contain class definitions.d)the body of the get_monthly_balance function should be added to the header file.

What is the difference between the internet and the world wide web?

Suppose a cpu with a write-through, write-allocate cache achieves a cpi of 2. what are the read and write bandwidths (measured by bytes per cycle) between ram and the cache? (assume each miss generates a request for one block.)