The new global satellite communications systems will offer three kinds of service, which may overlap in many different kinds of receivers.
VOICE. Satellite telephones will be able to make calls from anywhere on the earth to anywhere else. That could make them especially useful to remote, third world villages (some of which already use stationary satellite telephones), explorers and disaster-relief teams. Today’s mobile telephones depend on earth-bound transmitters, whose technical standards vary from country to country. So business travelers cannot use their mobile phones on international trips Satellite telephones would make that possible.
MESSAGING. Satellite massagers have the same global coverage as satellite telephones, but carry text alone, which could be useful for those with laptop computers. Equipped with a small screen like today’s papers, satellite messages will also receive short messages.
TRACKING. Voice and messaging systems will
A. laptop computer users
B. remote villages
C. disaster-relief teams
D. all above
The new global satellite communications systems will offer three kinds of service, which may overlap in many different kinds of receivers.
VOICE. Satellite telephones will be able to make calls from anywhere on the earth to anywhere else. That could make them especially useful to remote, third world villages (some of which already use stationary satellite telephones), explorers and disaster-relief teams. Today’s mobile telephones depend on earth-bound transmitters, whose technical standards vary from country to country. So business travelers cannot use their mobile phones on international trips Satellite telephones would make that possible.
MESSAGING. Satellite massagers have the same global coverage as satellite telephones, but carry text alone, which could be useful for those with laptop computers. Equipped with a small screen like today’s papers, satellite messages will also receive short messages.
TRACKING. Voice and messaging systems will
A. They are widely used.
B. They are very helpful.
C. They are costly.
D. Both A andB.
As we enter the 21st century, a new global economy draws nations ever closer. But our growing interdependence (21) on much more than technology and trade. For we are linked intrinsically by the physical and biological webs that (22) life on our planet -- and, increasingly, by the threat of their unraveling. Indeed, (23) we reach across borders and face this threat together, the next century may (24) an Earth in ecological crisis, with half of all (25) gone, and our grandchildren enduring deadly floods, drought and disease (26) by global warming.
When millions across America (27) the first Earth Day 30 years ago, our focus understandably was our own backyard. Our rivers were (28) on fire, and our skylines were disappearing behind a (29) of smog. American’s remarkable environmental progress in the years (30) is powerful testament to our national will, our technological prowess and our (31) in
A. since
B. between
C. from
D. lately
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