There Pictures from outer space now show us how much land has changed on earth. These images are taken by Landsat 7, a government satellite. The satellites have been used for 27 years. They reveal the clear-cutting of forests in the northwestern part of the United States. Pictures show the loss of rain forests in South America.
NASA’s Darrel Williams speaks about the Landsat 7 Project. He said that an eruption caused trees to bum up in a large forest. Fifteen years later, pinkish images from space show that the trees and plant life are growing again. Williams says that clear-cut areas easily show up in the pictures. He wants Americans to look at how much land is being cleared of forests in our country.
Satellites have provided other information about changes on earth. In the past ten years, more than four miles have shrunk from glaciers in Alaska. Landsat 7 received these computer images of Glacier Bay in Alaska.
Hurricanes Floyd and Irene have damag
A. a bright, white light that is reflected
B. little tiny trees that are growing
C. vegetable gardens that are planted
D. a light, pinkish view from space
There Pictures from outer space now
show us how much land has changed on earth. These images are taken by Landsat 7,
a government satellite. The satellites have been used for 27 years. They reveal
the clear-cutting of forests in the northwestern part of the United States.
Pictures show the loss of rain forests in South America. NASA’s Darrel Williams speaks about the Landsat 7 Project. He said that an eruption caused trees to bum up in a large forest. Fifteen years later, pinkish images from space show that the trees and plant life are growing again. Williams says that clear-cut areas easily show up in the pictures. He wants Americans to look at how much land is being cleared of forests in our country. Satellites have provided other information about changes on earth. In the past ten years, more than four miles have shrunk A. sightseers have noted the changes B. computer-animated views have shown the shrinkage C. one of the glaciers was hit by a ship D. the temperatures are much colder [单项选择]Let us now see how randomization is done when a collision occurs. After a ______, time is divided into discrete slots whose length is equal to the worst-case round-trip propagation time on the ether (2t). To accommodate the longest path allowed by Ethernet, the slot tome has been set t0 512 bit times, or 51.2μsec.A.slot B.switch C.process D.fire
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