1. What condition indicates that a linked list is empty? 2. The table below represents a portion of a computer's main memory containing a linked list. Each entry consists of two cells, the first being data, the second being a pointer to the next entry. If the nil pointer is represented by 00 and the list's head pointer contains 52, modify the memory cells so the data at address 50 is inserted as the second entry in the list. Address 50 51 52 53 54 55 56 57 58 59 Contents AA 00 BB 58 CC 00 DD 00 EE 54 3. Why is a queue normally implemented as a circular queue