The text's link-based queue is being used and holds an empty queue. We can say: Oat this point in time an invocation of the enqueue method would throw an exception. at this point in time an invocation of the dequeue method would throw an exception. the value of front is-1 O the numElements variable is null All of these are correct A glass queue is like a queue but: O it uses priorities. it allows enqueuing and dequeuing from both front and rear Oit keeps its elements sorted. O it allows peeking at front and rear elements None of these is correct