In the queue, the back pointer is important because:Ja$.$ without it$,$ we would have to walk a pointer through the entire queue toget to the last node, where we dequeueb. it makes it much easier to implement the deepCopy functionc. without it$,$ we would have to walk a pointer through the entire queue to get to the last node, where we enqueuewithout it$,$ we would have memory leak when the destructor is called