plzzz help me. in java it should all be in one program. plz help

1.3.19 Give a code fragment that removes the last node in a linked list whose first node is first.

1.3.21 Write a method find() that takes a linked list and a string key as arguments and returns true if some node in the list has key as its item field, false otherwise.

1.3.26 Write a method remove() that takes a linked list and a string key as arguments and removes all of the nodes in the list that have key as its item field.

starting from nothing