Secondary radar ______ these limitations but it depends on a transponder in the aircraft to respond to interrogations from the ground station to make the aircraft more visible and to report the aircraft's altitude.
【简答题】听对话,回答问题。 1. What does Ann often do on weekends? A. She often goes to the movies. B.She sings Beijing Opera. C. She stays at home. 2. Who wants to be a Beijing Opera artist? A. Ken. B. Ann. C. David.