1.Filltheblankswiththewordsorexpressionsgivenbellow.Changetheformwherenecessary.costconfirmcalloffgetovertakeoverpayneitherprivilegeaccountforresultin1.Oursloganisthat“quantityshouldneverbeincreasedattheof

Question

1.Fill the blanks with the words or expressions given bellow.Change the form where necessary.
cost confirm call off get over take over pay
neither privilege account for result in
1.Our slogan is that “quantity should never be increased at the _____ of the quality.”
2.The news of the air crash is not yet _____ by the government.
3.When Mr.Green retired,his son _____ the business.
4.I have two friends but _____ of them likes to go fishing with me.
5.His unhappy childhood _____ his bad temper.
6.The boy’s laziness _____ his failure in the exams.
7.Only guests of the hotel enjoy the _____ of using the private beach.
8.Tom _____ more than twenty pounds for the dictionary.
9.The governor had to _____ all his appointments for the day and rush to the train accident.
10.It took me a long time to ______ the disappointment of losing the match.
2.Put the following sentences into English.
1.每个人都是自己命运的主人.
2.以牙还牙.
3．事实胜于雄辩.
4．失败是成功之母.
5．欲速则不达.
6．笑到最后的人才是笑的最好的.
7．千里之行始于足下.
8．有其父必其子.
9.爱屋及乌.
10.人多好办事.
《概率与统计》作业
1．设随机变量X与Y相互独立,且X,Y的分布律分别为
X 0 1 Y 1 2
P P
试求：（1）二维随机变量（X,Y）的分布律；（2）随机变量Z=XY的分布律.
2．设P（A）=0.4,P（B）=0.5,且P（ ）=0.3,求P（AB）.
3．设随机变量X的概率密度为
试求：（1）常数c；（2）E（X）,D（X）；（3）P{|X-E（X）| < D（X）}.
4．一台仪器装有6只相互独立工作的同类电子元件,其寿命X（单位：年）的概率密度为
且任意一只元件损坏时这台仪器都会停止工作,试求：
（1）一只元件能正常工作2年以上的概率；
（2）这台仪器在2年内停止工作的概率.
5．用传统工艺加工某种水果罐头,每瓶中维生素C的含量为随机变量X（单位：mg）.设X~N（μ,σ2）,其中μ,σ2均未知.现抽查16瓶罐头进行测试,测得维生素C的平均含量为20.80mg,样本标准差为1.60mg,试求μ的置信度95%置信区间.
（附：t0.025(15)=2.13,t0.025(16)=2.12.）
6.设A、B为两个随机事件,0

Answer 1

作业不是要自己做的吗.