106. Low-orbit satellites are not used for communications because they
A. produce sonic booms
B. travel around the Earth too quickly
C. do not provide 24 hour/day contact to the users on Earth
D. heat up and melt

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107. Geosynchronous satellites are always launched in the equatorial plane because it is the only plane which provides
A. 24-hour orbit
B. stationary satellite
C. global communication
D. zero-gravity environs

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108. Depending on the technique used, digitized television requires a bit rate between millions
A. 40 and 92.5
B. 25 and 60
C. 30 and 82.5
D. 20 and 40

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109. A communication satellite is a repeater between
A. a transmitting station and a receiving station
B. a transmitting station and many receiving stations
C. many transmitting stations and many receiving stations.
D. all of the above

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110. The maximum signal propagation time of a geosynchronous satellite transmission is about millisecond.
A.540
B.270
C.135
D.1080

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111. A telephone user while talking to a person via a satellite has to wait for reply for about millisecond.
A.100
B.270
C.470
D.540

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112.  The echo heard by a telephone user on a satellite channel can be removed by using
A. a vocoder
B. a multiplexer
C. echo suppressor
D. digital techniques

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