搜题请搜索小程序“爱下问搜题”
问题 多项选择题

我国国家标准《故障树名词术语和符号》GB/T4888-85中规定的符号中，下列叙述正确的有（）。

A.矩形符号：代表顶上事件或中间事件

B.圆形符号：代表正常事件

C.房形符号：代表省略事件

D.椭圆形符号：代表条件事件

答案

参考答案：A, D

填空题
函数y=cosx的图象在点（
π
3
，
1
2
）处的切线斜率为______．
查看答案
单项选择题

If you are on the beach and are signaling to a small boat in distress that your present location is dangerous and they should land to the left，you would（）.

A.fire a green star to the left

B.send the letter K by light and point to the left

C.place an orange signal to your left as you signal with a white light

D.send the code signal S followed by L
查看答案