For the duties （）in one emergency, one person may do more than one job and one job may be done by more than one person.

Seven short blasts continued for one minute means （）.

A. fire alarm
B. boat alarm
C. man overboard
D. emergency alarm

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Several sand boxes need （）.

A. to repair and renew
B. repairing and renewing
C. repair and renew
D. repaired and renewed

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