True/False 15. _The following code is valid: int x =5; const int *ptr = &x; * ptr = 7; 16. _Comparing two pointers using relational op- erators are meaningful when both pointers point to elements of the same built-in array 17. _A pointer can be assigned to another pointer of the same type 18. Putting class definition in a separate file (e.g. header) makes it easy to reuse. 19. _A member function of a class can access pri- vate data members of the same class. 20. _Each object of a class has same number of data member and same variable name but different memory location for each data member