Passage 2
Early in the 16th century men were trying to reach Asia by traveling west from Europe. In order to find Asia they had to find a way past South America. The man who eventually found the way from the Atlantic Ocean to the Pacific was Ferdinand Magellan. Magellan sailed from Seville in August 1519 with five ships and about 280 men. Fourteen months later, after spending the severe winter on the coast of Patagonia, he discovered the channel which is now called Magellan’s Straits. In November 1520, after many months of dangers from rocks and storms, the three remaining ships entered the ocean on the other side of South America. They then continued, hoping to reach Asia. But they did not see any land until they reached the islands off the coast of Asia. Before they arrived at these islands, later known as the Philippines, men were dying of starvation. While they were staying in the Philippines, Magellan was killed in battle. The remaining officers then had to get
A. pass the Pacific
B. cross South America by land
C. find a way from the Atlantic Ocean to the Pacific
D. build ships
Passage Three
In early 2004 eight tiny sensors were dropped from a plane near a military base in California. After hit ting the ground, the sensors—also known as smart dust sensors organized themselves into a network and quickly detected a fleet of military vehicles on the ground. They determined the direction, speed and size of a series of military vehicles traveling along the road and later transmitted the data to a computer at a nearby base camp.
Smart dust sensors are minicomputers—as small as a grain of rice in some cases—that can monitor and evaluate their physical environment and can relay the information via wireless, communication. They can monitor elements such as temperature, moisture, humidity, pressure, energy use, vibration, light, motion, radiation, gas, and chemicals. These devices will soon have many applications, such as use in emergency rescue.
Software has been developed to run these minicomputers. A key feature
A. giving troops their protective gear
B. organizing themselves into a computer network
C. detecting the movement of military vehicles nearby
D. operating in remote and dangerous War zones
| We sometimes think humans are uniquely
vulnerable to anxiety, but stress seems to affect the immune defenses of lower
animals too. In one experiment, for example, behavioral immunologist (免疫学家) Mark
Laudenslager, at the University of Denver, gave mild electric shocks to 24 rats.
Half the animals could switch off the current by turning a wheel in their
enclosure, while the other half could not. The rats in the two groups were
paired so that each time one rat turned the wheel it protected both itself and
its helpless Partner from the shock. Laudenslager found that the immune response
was depressed below normal in the helpless rats but not in those that could turn
off the electricity. What he has demonstrated, he believes, is that lack of
control over an event, not the experience itself, is what wakens the immune
system. Other res A. the sweetener was poisonous to them B. their immune systems had been altered by the mind C. they had been weakened physically by the saccharin D. they had taken too much sweetener during earlier conditioning 我来回答: 提交
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