简述梅毒的报告要求。
如果删除了公式中使用的单元，则该单元显示（）。 ###。 ？。 #REF！。 以上都不对。
why should the SES operators be very careful when the ship enters the area where three ocean regions overlap? Because（）. the weather over there is always terrible。 the condition there is complicated。 the signals are too strong。 their SES may receive the signals from unwanted satellite。
门诊日志的主要内容有哪些？
尼龙带的抗拉力为（）。 5kN。 10kN。 15kN。 20kN。
The quality of EGC messages is（）affected by the position of the ship, the time of reception and climatic conditions.
