Data structures: java

7. Suppose we implement a stack using a partially-filled array. What is wrong with storing the top-of-stack at location [0] and the bottom of the stack at the last used position of the array? 8. If we use a linked list with a head and a tail reference to implement a stack, which is better and why? Having the top-of-stack at the head of the linked list, or having the top-of-stack at the tail of the linked list?