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單項(xiàng)選擇題

It is quite（）for an SES operator to send a distress alert.

A.easy and expensive
B.simple and certain
C.dangerous and stable
D.difficult and compulsory

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單項(xiàng)選擇題

In which year was the COSPAS-SARSAT system established?（）

A.1980
B.1981
C.1979
D.1982

單項(xiàng)選擇題

When receiving a distress alert, the SAR authorities ashore and the ships in the vicinity of the ship in distress will（）in a coordinated search and rescue operation with the minimum delay.

A.assist
B.send a rescue vessel
C.search the distress area
D.reach the distress position at once