Answer:
1st is a armed head, the message is to beware of macduff. "macbeth,macbeth beware macduff"
2nd is a bloody child that says "none of woman born shall harm Macbeth"
3rd is a child crowned with a tree in his hand and the child represents malcolm, king Duncan's child and the tree shows how Malcolm's army will camouflage as it approaches Macbeth's castle. :) hope these helped