Which methods should probably be implemented first in order to make it easier to test other methods? isEmpty and size0) add and remove remove and toArray add and toString What is the purpose of the described private shiftRight() method in the array-based implementation of List? It makes sure that the size of the array is at least DEFAULT_CAPACITY. It is used when adding an element to the middle of the list. It sets the size of the array to MAX_CAPACITY It doubles the size of the array when the array is too small