A、3-6 months of monthly salary B、13% of their monthly salary C、10 dollars a week D、36% of their monthly salary A细节题．对话中女士提到，一个人应

M: Do you think people today do a good job of planning for financial emergencies?
W: Well, I think most people want to have a secure future. Um, however, the information they need to achieve financial security isn’t at their fingertips. For example, well, they need to establish their goals, for instance, how much money do they need to live?
M: Then how much money do you think people need to save for themselves?
W: Well, the thing is, you should have 3-6 months of monthly salary saved, so whatever your monthly salary is, you should have enough to pay your expenses for 3-6 months without any income.
M: And then in addition to that, most of us need to plan for college, retirement, taking care of parents, etc.
W: Uh-huh. And the kinds of things that rise up unexpectedly, for example, like the water heater blowing up or the car not starting in the morning.
M: So, what’s the biggest mistake people make?
W: Well, they tend to live from paycheck to paycheck. And when something unexpected occurs, if they don’t have someone to help, they just go deeper and deeper into debt, then fall farther and farther behind their payments.
M: So, if you could give people one piece of advice to make their financial future more secure, what would you suggest?
W: The best advice I can give is that "Pay yourself first". When you get your paycheck, save some portion of it, even $ 10 a week. That’s giving up a movie or one stop at a fast food restaurant.
Questions:
19. According to the woman, how much money should people save for themselves?
20. What’s the biggest mistake people make in the aspect of finance?
21. What does "Pay yourself first" refer to?