话音信号的主要能量集中的频率范围是（）赫兹。

PIL：Tower G-ABCD, radio check 118.7. CTL：Station calling Tower, （ ） unreadable.

CTL：CSN108, （ ） , CSN308, readability 5.

Hong Kong Delivery, CSN308, radio check 124.65, how do you （ ） .

In which case is a controller supposed to say CORRECTION?

Radio check requirement order is （ ） .

The abbreviated call sign of TWA NGPED is （ ） .

In RTF communication, the aircraft call sign 9099X is spoken as （ ） .

Prior to starting transmission, a pilot or controller should （ ） .

When visibility is lower than （ ）meters, tower controller should report RVR to pilots..

（ ） should make the final decision of landing or going around and be responsible for it.