When Christie Andrews was born, she weighed less that half of one kilogram. Her heart was the size of a large coin. Her mother said Christie was so small that she could hold her in the palm of one hand.
Christie couldn’t breathe without a machine to give her oxygen. If she had been born 20 years earlier, she would probably have died at once. She needed two operations, but she survived without serious damage.
Twenty years ago , 90% of all premature(早产) babies died. Today, doctors manage to save four out of every five, because they have better machines for breathing and better ways to feed the babies.
But saving Christie’s life cost more than $ 400,000. In some cases, doctors spend 1 million dollars saving a single child. The parents usually don’t have enough money to pay. The government, an insurance company or the hospital picks up the bill. Even after a baby goes home from the hospital, it may require medical care.
Some people think it makes more sense to spend money saving 10 adults who have cancer or other diseases than saving one small baby. But nobody wants to be the doctor who has to tell parents to their faces, “Sorry, I won’t save your new child.”
【小题1】 Parents don’t pay their babies’ hospital bills because        .

When an animal helps another animal, it usually gets something valuable in return. For a long time, many scientists thought that only people could act generously just because it feels good.
However, a new study in Germany suggests that chimpanzees (黑猩猩)also do good things for no real reason. And so do children who are as young as 18 months of age. Maybe it is because humans and chimpanzees share an ancestor(祖先) about 6 million years ago.
People and chimpanzees appear to develop such features(特征) without any other training, says Warneken, a scientist in Germany. Warneken and his partners worked on adult chimpanzees that live on an island in the African country of Uganda. They also worked with 18-month-old children in Germany. The researchers performed three experiments on the adult chimpanzees and two experiments on the kids. In the first animal experiment，a person tried to reach his arm into a cage to get a stick，but he couldn’t reach it. A chimpanzee was in the cage，and it could reach the stick if it wanted to.
Thirty-six chimpanzees took part in this experiment one by one, and no chimpanzee saw what the other chimpanzees had done. Even though the animals hadn’t met the person before, they usually took the stick and gave it to the person. What’s more, they did this whether or not the person offered them bananas as a reward. In a similar experiment, 36 children acted in a similar way. They helped the person reach the stick, whether or not they were offered toys for their help.
Researchers did other experiments on chimpanzees and babies. No rewards were offered in either experiment. And still, both the chimpanzees and children went out of their way to help. Still, the new study is different from earlier findings. Researchers have found that chimpanzees don’t give rewards of food to other chimpanzees, even if it costs them nothing to be generous.
【小题1】Warneken and his partners worked with ________.