Lesson 4 short exchange listening-1
A. 121.9
B. loud and clear
C. 5
D. 129.0
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Lesson 4 short exchange listening-2
A. GABCD’s voice is perfectly readable
B. GABCD’s transmission is hard to understand
C. He can not hear what GABCD says
D. The crew’s transmission is broken
Lesson 4 short exchange listening-3
A. in and out
B. loud and clear
C. unreadable
D. readable but with difficulty
Lesson 4 short exchange listening-4
A. due squawk noise
B. due background whistle
C. due broken transmission
D. due unreadability
Lesson 4 short exchange listening-5
A. Due fast speed
B. due broken transmission
C. due unstable signal
D. due background whistle
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