Answer:
they frame King Duncan's servants for the murder
The child is the father to the man means that we will find the basic personality of the adult nascent in the child. Is the child honest, extroverted, sly, cautious, thoughtful? Driven to succeed? Driven for approval? Fatalistic? You will likely find that when he is an adult he will embody much the same character.
Faustus and the German emperor have always been enemies
The emperor is more powerful than Faustus
Faustus once declared that he will rule Germany
Faustus has already declared himself the new emperor of Germany