Question 26 1 pts Which is NOT an important characteristic of heap variables? There is more space available on the heap than the stack O heap variables must be explicitly deleted it's preferable to create arrays and class instances on the heap O heap memory is automatically reallocated when the variable goes out of scope Question 27 1 pts When a class has member variables on the heap, what else should it do? have a copy constructor to ensure new copies of the class have their own instances have a destructor to ensure the heap variables are released both of the above O neither of the above Question 28 1 pts What's the difference between a deep and shallow copy? a deep copy is much more profound than a shallow copy a deep copy explicitly creates new instances of heap variables O a shallow copy always has an explicitly defined copy constructor a shallow copy copies only methods, not instance variables