在容器、槽箱内工作，如需站在梯子上工作时，工作人员应使用安全带，绳子的一端拴在（）。
A、外面牢固的地方
B、容器人孔盖上
C、梯子上
参考答案：A
How can rescue personnel detect that a SART is transmitting in the immediate vicinity?（）
A.The SART's blips on the PPI will begin arcing and eventually become concentric circles
B.The DSC unit will react to the SART's signal and respond with the two-tone alarm
C.The SART can provide an approximate location to within a two nautical mile radius，per IMO standards
D.The SART signal appears as a target which comes and goes; the effect of heavy swells on a SART
下列有关DNA双螺旋结构主链特征的表述中哪一项是错误的？（）
A.由脱氧核苷酸与磷酸交替排列而成
B.两条主链方向相反但保持平行
C.两条主链按一定的规则盘绕成双螺旋
D.排列在双螺旋的外侧且极为稳定
