题目内容
| A．Human efforts to prevent disastrous collisions B．Recent alarms of asteroid(小行星) strikes． C．Asteroids’ movement around the sun． D．Asteroid strikes against Earth． E．Past disastrous asteroid strikes． F．The cause of asteroid strikes． |
76._________________
Astronomers estimate that there are about l,100 asteroids--or space rocks--with the potential to cause a planet-wide disaster in a collision with Earth．And since large asteroids have collided with Earth many times in the past，scientists say it is certain that Earth will be hit again．It is only a question of when．
77. _________________
The asteroid that ended the age of the dinosaurs hit the Earth 65 million years ago．It was at least six miles(10 kilometers)wide．But smaller asteroids can also devastate （毁坏）the earth．Scientists estimate that a collision with an asteroid even one—tenth this size would kill at least 25 per cent of Earth’s population．Less than a hundred years ago，for example，an asteroid only 330 feet(100 meters)wide exploded in Siberia．It completely destroyed half a million acres of forest．
78．_________________
Asteroids come from a belt of tens of thousands of space rocks in orbit around the sun．They normally travel between Mars and Jupiter，but some smaller rocks are affected by the gravitational pull of Mars，Jupiter or Saturn and their orbits are stretched．Sometimes this change puts them on a path that crosses Earth’s orbit．This sets up the possibility of collision with Earth．
83．_________________
In l986，a potentially dangerous asteroid missed Earth by only six hours．Scientists only found out about the danger after it had passed．Many more asteroids have collided with Earth over the years．We can still see their marks today — large craters in the ground．
79．_________________
NOW there is a new--found seriousness about asteroid strikes．Astronomers are engaged in a painstaking search for all asteroids that threaten Earth．And the United States has a project called NEAR that involves orbiting and studying the asteroid Eros，the second largest asteroid near Earth．Studying the composition of the asteroid provides important information hat may allow an asteroid to be exploded or knocked of course to prevent it from colliding with Earth．
76. D 77.E 78.F 79.B 80.A
名师指导期末冲刺卷系列答案Dogs have an understanding of fair play and become angry if they feel that another dog is getting a better deal, a new study has found.
The study looked at how dogs react when a companion is rewarded for the same trick in an unequal way. Friederike Range, a researcher at the University of Vienna in Austria, and her colleagues did a series of experiments with dogs who knew how to respond to the command “give the paw “. The dogs were normally happy to repeatedly give the paw, whether they got a reward or not. But that changed if they saw that another dog was being rewarded with a piece of food, while they received nothing.
“We found that the dogs hesitated significantly longer when obeying the command to give the paw,” the researchers write. The unrewarded dogs eventually stopped cooperating.
Scientists have long known that humans pay close attention to inequity. But researchers always assumed that animals didn’t share the trait. “The argument was that this is a uniquely human phenomenon,” says Frans de Waal, a professor of psychology at Emory University in Atlanta.
That changed in 2003 when he and a colleague did a study on monkeys. The monkeys had to hand a small rock to researchers to get a piece of cucumber in return. They were happy to do this. But if they saw that another monkey was getting a more delicious reward, a grape, for doing the same job, they would throw away the food and rock, and at some point just stopped performing.
In that experiment, the monkeys considered the fairness of two different types of payment. But when Range and her colleagues did a similar study with their trained dogs, testing to see if dogs would become upset if they only got dark bread when other dogs received sausage, they found that as long as the dogs got some kind of food payment, even if it wasn’t the most delicious kind, the animals would play along.
【小题1】How did the dogs in Range’s study react to the order of “giving the paw”?
| A．They took the order even without being rewarded. |
| B．They took the order only when rewarded. |
| C．They turned a deaf ear to repeated orders. |
| D．They hesitated longer when given repeated orders. |
| A．originated from Range’s research on dogs. |
| B．showed that animals do pay attention to inequity. |
| C．began the argument that only humans are aware of inequity. |
| D．was conducted to find out how monkeys reacted to humans’ orders. |
| A．was given less work. |
| B．was given more food. |
| C．was given the same type of food. |
| D．was given more delicious food. |
| A．care more about whether they are rewarded. |
| B．care less about what they are rewarded with. |
| C．care more about what they are ordered to do. |
| D．care less about who gives them orders. |
| A．Animals have various ways to show their anger. |
| B．Dogs are less intelligent than monkeys. |
| C．Dogs have a sense of fairness. |
| D．Most animals want to be rewarded equally. |
Directions: Read the following text and choose the most suitable heading from A – F for each paragraph. There is one extra heading which you do not need.
E．Past disastrous asteroid strikes． F．The cause of asteroid strikes． |
76._________________
Astronomers estimate that there are about l,100 asteroids--or space rocks--with the potential to cause a planet-wide disaster in a collision with Earth．And since large asteroids have collided with Earth many times in the past，scientists say it is certain that Earth will be hit again．It is only a question of when．
77. _________________
The asteroid that ended the age of the dinosaurs hit the Earth 65 million years ago．It was at least six miles(10 kilometers)wide．But smaller asteroids can also devastate （毁坏）the earth．Scientists estimate that a collision with an asteroid even one—tenth this size would kill at least 25 per cent of Earth’s population．Less than a hundred years ago，for example，an asteroid only 330 feet(100 meters)wide exploded in Siberia．It completely destroyed half a million acres of forest．
78．_________________
Asteroids come from a belt of tens of thousands of space rocks in orbit around the sun．They normally travel between Mars and Jupiter，but some smaller rocks are affected by the gravitational pull of Mars，Jupiter or Saturn and their orbits are stretched．Sometimes this change puts them on a path that crosses Earth’s orbit．This sets up the possibility of collision with Earth．
79．_________________
In l986，a potentially dangerous asteroid missed Earth by only six hours．Scientists only found out about the danger after it had passed．Many more asteroids have collided with Earth over the years．We can still see their marks today — large craters in the ground．
80．_________________
NOW there is a new--found seriousness about asteroid strikes．Astronomers are engaged in a painstaking search for all asteroids that threaten Earth．And the United States has a project called NEAR that involves orbiting and studying the asteroid Eros，the second largest asteroid near Earth．Studying the composition of the asteroid provides important information hat may allow an asteroid to be exploded or knocked of course to prevent it from colliding with Earth．