阅读理解。
There's a story told about an elderly lady in Arkansas. The state voted to increase welfare payments
to the poor. Hoping for a tear-jerker story,a television interviewer went into the back hills where many
welfare recipients(接受者)lived.
The old woman he chose to interview lived in a one-room shack(棚屋):cold in winter；hot in
summer. Her bed was a few rough planks(厚板)nailed together,with a pine-needle mattress. A couple
thin blankets,and a fireplace,did little to protect her from the cold.
Her furniture,a table and two chairs,were fashioned from the same rough wood as her bed. Some
shelves held a few cans of food from the general store. a three mile walk down the road. Several jars
of preserves and a few squash(南瓜类蔬菜)completed her larder(食品室).
She had no fridge or freezer. The fireplace provided heat for cooking. With no phone or television
her only connection with the outside world was an old radio that pulled in two or three local stations on
a good day.
The old woman had one convenience, running water. A crystal clear stream. flowed a short distance
behind her home.
A small garden near her back door provided fresh vegetables during the summer,and some squash
and turnips for the winter. A tidy flower garden brightened the front of her house.
The television crew arrived and set up their big expensive cameras. Their mobile station. broadcast
pictures of the woman and the place she called home.
Eventually the interviewer asked the old woman,"If the government gave you $200 more each month,
what would you do with it?"
Without hesitation the woman replied,"I'd give it to the poor. "
1. How did the woman get water?
A. From the tap.
B. From a stream.
C. From a spring.
D. From a well behind her house.
2. Which of the following statements is TRUE about the old lady's living conditions?
A. Her furniture was very fashionable though simple.
B. Her fireplace couldn't keep her warm enough in winter.
C. She could get in touch with outside world by radio easily.
D. She couldn't get fresh food without fridge or freezer.
3. What do we know about the woman?
A. She must he content with her life.
B. She knows nothing about the outside world.
C. She is living a lonely and miserable life.
D. She must be better-off than many others in the area.
4. Which of the following word can best describe the woman?
A. Generous.
B. Ignorant.
C. Out of mind.
D. Noble-minded.
5. It can be inferred from the passage that .
A. the interviewer got a story beyond his expectation
B. the interviewer was very disappointed with the woman
C. the woman became famous because of the interview
D. the interview became a turning. point in the woman's life
。 
，在0℃的长度分别为L10和L20，若发现这两根金属棒在任何温度下长度之差均恒定，求
之比为多少？