Answer:
The mysterious and disfigured Mr. Steward arrives to deliver the key to unlock the button, and tells Norma that if the button is pushed, she will receive $1 million in cash, but someone she does not know will die. He gives her $100 for allowing him to enter the house and voice his deal, and leaves.
Answer:
IT IS BEACUSE HEY ADOPT THIS HABIT OF SHAKING
When Lady Macbeth dies, he feels nothing, he is emotionless. That might tell us that she has turned him into a ruthless killer, who will stop at nothing to get what he wants, and what he wants is the kingdom. He is very calm, as if he doesn't care at all that his wife died - she has turned him into a mad monster. He has lost all ability to feel, at least until he finishes what he has started.