In C++ format: The following class keeps track of how much of a memory block (say, 512 bytes) is being used. It contains a pointer that will point to the first element of an array. This array will be of an arbitrary size. There is a second integer to hold the size (as given by the user at the time of instantiation). Each element of the array is a block, and the number kept in that element is the bytes of that block used. class BlockUsage t private: int* blocks; int numBlocks public: // constructors (default, one arg, and copy) BlockUsage ) BlockUsage (int); BlockUsage (const BlockUsage&) // destructor BlockUsage () // Member function int blockAtIndex (int); i) If this is in the Class Specification file (BlockUsage.h), write the function definitions that would be in the Class Implementation file (BlockUsage.cpp). For the default constructor. NULL and 0 are appropriate default values. ii) Why must the parameter of the copy constructor be of type constant reference