“观察旅客情况,查看携带物品,制止违禁物品进站”属于汽车客运站哪个岗位的工作职责()。
A、值班站长
B、广播员
C、迎门服务员
D、问事处服务员
参考答案:C
极差是数据离散趋势的特征值之一,是数据中最大值与最小值之差,它的作用为( )。
A.用数据变动的幅度来反映其分散状况的特征值B.反映数据变异程度的特征性C.表示数据的相对离散波动程度D.表示数据的代表性
For an activity,the optimistic,most likely and pessimistic estimates are 12,16 and 18 respectively.Which of the following statement is correct ?()
A.There is 68.26% chance that the activity will be completed in 15 to 17 day
B.There is 95.44% chance that the activity will be completed in 15 to 17 day
C.There is 68.26% chance that the activity will be completed in 14.67 to 16.67 day
D.There is 93.73% chance that the activity will be completed in 15 to 17 day