Question # 2 Multiple Select
Which statements are true? Select 4 options.

An instance of a class cannot be changed after it is created.

Variables defined in the constructor of a class can be accessed by the main program that uses instances of the class.

Functions defined in a class are called methods.

A class variable can be a different type of class.

A class variable can be a list of instances of a different class.

The can be used to paste text in any order

1)consider the following code snippet: #ifndef book_h#define book_hconst double max_cost = 1000.0; class book{public: book(); book(double new_cost); void set_cost(double new_cost); double get_cost() const; private: double cost; }; double calculate_terms(book bk); #endifwhich of the following is correct? a)the header file is correct as given.b)the definition of max_cost should be removed since header files should not contain constants.c)the definition of book should be removed since header files should not contain class definitions.d)the body of the calculate_terms function should be added to the header file.

Least square fit to polynomial write a function leastsquarefit3pol that solves a linear system of equations to find a least squares fit of a third order polynomial to an experimental data set given as two row arrays. the function leastsquarefit3pol must explicitly solve a set of linear equations and cannot use polyfit. there should be no restriction on the size of the problem that can be solved.