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單項選擇題

It is（）for mariners to combine the SART with a float-free satellite EPIRB.

A.essential
B.compulsory
C.optional
D.inadvisable

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單項選擇題

（）is a space system using one or more artificial earth satellites.

A.Satellite network
B.Satellite link
C.GMDSS
D.Satellite system

單項選擇題

For ships equipped with an SES, it is（）and（）for the operator to send a distress alert.

A.easy/reliable
B.difficult/cheap
C.stable/compulsory
D.easy/expensive

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