B. the term “ranging” used for detection of the distance between an object and the radar set
C. the time it takes for the radio waves to produce echoes and bounce off the object
D. the time it takes for the echoes produced by the radio waves to return to the radar set
Chọn D
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People don’t want to buy cars with large engines any more. (call)
→ There isn’t ______________________________________.
Fill each blank with a suitable word or phrase.
The car can't have broken down. I_________ serviced last week.