问题详情

How should you signal the crane operator to raise the boom?().


A、Extend arm with the thumb pointing up and flex the fingers in and out

B、Place both fists in front of the body with the thumbs pointing upward

C、With forearm vertical and forefinger pointing up,move hand in small horizond circles

D、Extend arm with the fingers closed and thumb upward

时间:2022-01-10 13:30 关键词: 航海英语综合练习

答案解析

D