Trace a queue (called Q) through the following operations: Queue Q = new Queue (); Q middot enqueue (new Integer (3)); Integer X = Q middot dequeue (); Q. enqueue (new Integer (12)); Q middot enqueue (new Integer (5)); Q middot enqueue (new Integer (1)); Integer Y = Q middot first (); Q middot enqueue (new Integer (9)); Integer Z = Q middot dequeue (); What is the value of Y after it has been assigned? Give the contents of the queue after the code has been executed. Indicate the elements in order and label the front