【判断题】若X,Y独立,则E(XY)=E(X)E(Y)
【单选题】What does the author think of teaching ability?
A.
It requires talent and practice.
B.
It is closely rela t ed to research.
C.
It is a ch i ef fac tor affecting students 'learning.
D.
It can b e ac qu i re d through pe r sistent practice.
【单选题】What does” the first basics of teamwork” refer to?
A.
The OOW works only person on the bridge
B.
The OOW has to follow the standing order
C.
The OOW calls watch stander a an lookout
D.
The OOW takes personally responsible for all aspects of rate navigation
【简答题】现实的人力资源数量由适龄就业人口、______________、老年就业人口数量构成。
【简答题】( )是性质相同的数据元素的集合,是数据的一个子集。
【单选题】数据对象是一组性质相同的数据元素的集合。
【简答题】在sheetl工作表中建立如下内容工作表,并用公式求出每人的总评成绩,总评=平时 x30%+期末×70%,表中字体设为楷体16磅,数据水平居中,垂直居中,表标题合并居中、20磅、蓝色字,并将工作表命名为“成绩表”。 2. 将成绩表复制为一张新工作表,将期末成绩在80分到89分的人筛选出来,并将工作表命名为“筛选”保存在EX6.XLS中。
【单选题】What does the author say about deep wells?
A.
They run without any need for repairs.
B.
They are entirely free from pollutants.
C.
They are the ultimate solution to droughts.
D.
They provide a steady supply of freshwater.
【单选题】在EXCEL中,若一个工作簿有4个工作表,其中一个的名字是ABC,复制这个工作表后(建立副本),新的工作表名是____