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【单选题】
B-trees have small height so as to B树的层数少有助于:
A.
reduce the number of I/O operations 减少I/O次数
B.
reduce the time consumption for a single I/O 减少每次I/O的时间
C.
reduce the asymptotic time complexity for seaching 降低查找的渐进时间复杂度
D.
reduce the storage requirement 节省存储空间
参考答案:
参考解析:
.
刷刷题刷刷变学霸
举一反三
《危险化学品企业特殊作业安全规范》关于吊装作业,下列说法不正确的是:( )
A.
吊物接近或达到额定起重吊装能力时,应检查制动器,用低高度、短行程试吊后,再吊起
B.
停工和休息时,可以暂时将吊物、吊笼、吊具和吊索悬在空中
C.
不应在起重机械工作时对其进行检修;不应有载荷的情况下调整起升变幅机构的制动器;
D.
下放吊物时,不应自由下落(溜);不应利用极限位置限制器停车
《危险化学品企业特殊作业安全规范》临时用电应符合:( )
A.
火灾爆炸危险场所应使用相应防爆等级的电气元件,并采取相应的防爆安全措施
B.
临时用电线路及设备应有良好的绝缘,所有的临时用电线路应采用耐压等级不低于380V的绝缘导线
C.
临时用电线路经过火灾爆炸危险场所或有高温、振动、腐蚀、积水及产生机械损伤等区域,可有接头,但应采取相应的保护措施;
D.
临时用电设施应安装符合规范要求的漏电保护器,移动工具、手持式电动工具可根据实际情况配置漏电保护器和电源开关。
《危险化学品企业特殊作业安全规范》在夜间或雨、雪、雾天进行断路作业时设置的道路作业警示灯,警示灯设置错误的是:( )
A.
采用220v电压
B.
设置高度应离地面1.5 m,不低于1.0 m
C.
其设置应能反映作业区域的轮廓
D.
应能发出至少自150 m以外清晰可见的连续、闪烁或旋转的红光
《危险化学品企业特殊作业安全规范》作业监护人承担的职责有()
A.
作业前检查安全作业票。安全作业票应与作业内容相符并在有效期内;核查安全作业票中各 项安全措施已得到落实。
B.
确认相关作业人员持有效资格证书上岗。
C.
核查作业人员配备和使用的个体防护装备满足作业要求。
D.
对作业人员的行为和现场安全作业条件进行检查与监督,负责作业现场的安全协调与联系。
《危险化学品企业特殊作业安全规范》关于受限空间作业监护,下列说法正确的是( )
A.
监护人应在受限空间外进行全程监护
B.
不应在无任何防护措施的情况下探入或进入受限空间;
C.
在风险较大的受限空间作业时,应增设监护人员,并随时与受限空间内作业人员保持联络;
D.
监护人应对进入受限空间的人员及其携带的工器具种类、数量进行登记,作业完毕后再次进行 清点,防止遗漏在受限空间内。
根据《危险化学品企业特殊作业安全规范》,关于受限空间作业,下列说法正确的是( )
A.
作业前60 min内,应对受限空间进行气体采样分析,分析合格后方可进入
B.
检测点应有代表性,容积较大的受限空间,应对上、中、下(左、中、右)各部位进行检测分析;
C.
作业现场应配置移动式气体检测报警仪,连续检测受限空间内可燃气体、有毒气体及氧气 浓度,并2 h记录1次;
D.
作业中断时间超过60 min时,应重新进行气体检测分析。
《危险化学品企业特殊作业安全规范》直接引起坠落的客观危险因素有()。
A.
阵风风力五级(风速8.0m/s)以上
B.
阵风风力五级(风速10.0m/s)以上
C.
平均气温等于或低于5℃的作业环境
D.
平均气温等于或低于10℃的作业环境
《危险化学品企业特殊作业安全规范》盲板及垫片应根据管道内介质(  )等选择相应材料选用合适的材料制作。 
A.
 性质        
B.
 压力       
C.
 温度       
D.
管道法兰密封面的口径
《危险化学品企业特殊作业安全规范》以下属于司索人员职责的有()
A.
听从指挥人员的指令,并及时报告险情;
B.
不应用吊钩直接缠绕吊物及将不同种类或不同规格的索具混在一起使用;
C.
吊物就位时,应与吊物保持一定的安全距离,用拉绳或撑杆、钩子辅助其就位;
D.
吊物就位前,不应解开吊装索具;
相关题目:
【单选题】In the Academic Writing part, Alex discussed with Ruoqi on academic skills, such as ______.
A.
plagiarism, paraphrasing and summarizing
B.
plagiarism, paraphrasing and synthesizing
C.
how to avoid plagiarism, paraphrase and summarize
D.
how to avoid plagiarism, paraphrase and synthesize
【多选题】运动休闲可以( )。
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减轻医疗负担
B.
增强抵抗力
C.
减少疾病
D.
促进心理健康
E.
缓解精神压力
【单选题】Through the group discussion between ______ , we figured out the differences between adolescence and adulthood.
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Abbas, Zuowan and Jialin
B.
Billy, Xuanhui and Jialin
C.
Abbas, Xuanhui and Jialin
D.
Billy, Xuanhui and Zixiao
【单选题】下面说法正确的是
A.
FileWriter类是Writer类的子类
B.
FileWriter类是OutputStreamWriter类的子类
C.
FileWriter类是FileOutputStream类的子类
D.
Wirter类是OutputStreamWriter类的子类
【单选题】What's the return value for a failed search in a B-tree of order 4?B树查找算法若最终失败,返回值为:
A.
None
B.
NULL
C.
A pointer to the last examined node 指向最后一个所查找节点的指针
D.
A pointer to the root 指向根节点的指针
【单选题】Which of the following is NOT the reason why she does not like to take photos with the camera?
A.
It was easy to break
B.
It was too heavy
C.
it is easy to get stolen
D.
it is too expensive
【单选题】What “eat earth” means?
A.
Having to spend less after spending a lot during the shopping festival.
B.
Living a luxurious life after earning a lot of money.
C.
Having failed to live a modest life.
D.
Living a luxurious life.
【单选题】Popular novels can be adapted and made into ____; ____ and _____.
A.
films; television programs; video games
B.
cartoons; dramas; games
C.
websites; televisions; audio programs
D.
films; cartoons; games
【单选题】下面说法中错误的是
A.
FileReader类是Reader类的间接子类
B.
InputStreamReader类是Reader类的子类
C.
BufferedReader类可以读取一行
D.
BufferedReader的readLine()函数,如果没有数据时会返回0
【单选题】What's the 'overflow' for a B-tree?B树的上溢是指:
A.
The property of a B-tree is violated due to removing a key 删除关键码后违反了B树的性质
B.
The property of a B-tree is violated due to inserting a key 插入新的关键码后违反了B树的性质
C.
The property of a B-tree is violated due to a split 分裂后违反了B树的性质
D.
A B-tree becomes too high B树的高度过高
【单选题】设随机变量服从区间(0,2)上的均匀分布,则$Y=X^{2}$在(0,4)上的密度函数为()
A.
$\frac{1}{3\sqrt{y}}$
B.
$\frac{1}{\sqrt{y}}$
C.
$\frac{1}{2\sqrt{y}}$
D.
$\frac{1}{4\sqrt{y}}$
【单选题】Which consequence follows as a B-tree becomes higher?B树高度的增加一定伴随着:
A.
Each node has a larger number of keys 每个节点所存放的关键码数量增加
B.
Each node has a smaller number of keys 每个节点所存放的关键码数量减少
C.
Splitting to the root 分裂到根
D.
Splitting to the leaves 分裂到叶
【多选题】Gardening is ______.
A.
a great daily exercise
B.
a great way to keep your lawn beautiful
C.
a great way to keep you healthy
D.
landscape painting
【单选题】Choose the most appropriate answer by completing the sentences below or answering the questions.1. Why is Billy a bit disappointed about the film?
A.
The quality of the film is comparable with the novel itself.
B.
The movie is unbelievable, for the plot is not true to the novel.
C.
The stories producers and directors tell are unbelievable.
D.
While adapting the original novels into films, producer exaggerated too much.
【单选题】The differences between the original novel and their adapted film depend on _______, _______ and _______.
A.
writers; actors; audience
B.
writers; actors; producers
C.
directors; actors; audience
D.
directors; producers; audience
【单选题】The underflow of a B-tree happens whenB树的下溢发生于:
A.
the height of the tree decreases B树高度减少
B.
the property of the B-tree is violated due to inserting a key 插入关键码后违反了B树的性质
C.
the property of the B-tree is violated due to deleting a key 删除关键码后违反了B树的性质
D.
inserting a key to a leaf node 在叶节点插入关键码
【单选题】The height of a B-tree decreases only whenB树高度的减少只会发生于
A.
merging two children of the root 根节点的两个孩子合并
B.
removing the root 根节点被删除
C.
rotating the root 根节点发生旋转
D.
there are multiple keys in the root 根节点有多个关键码
【单选题】Why do Amanda and Zheyu feel very down today?
A.
They are worried about homework.
B.
They are worried about exams.
C.
They are worried about interviews.
【多选题】以下哪种说法是正确的——
A.
人生观是对人生目的、意义的根本看法
B.
世界观是人生观重要组成部分
C.
价值观是人生哲学的核心,是人与人之间对于人生价值的不同看法
D.
哲学只是关于世界观的学问
【单选题】What does “be apt to do something” mean?
A.
be more likely to do something
B.
be angry to something
C.
be happy to do something
D.
be taught to do something
【多选题】A node in a red-balck tree could be红黑树节点的颜色有
A.
red 红
B.
black 黑
C.
yellow 黄
D.
blue 蓝
E.
green 绿
F.
purple 紫
【多选题】被称为中国新四大发明的有哪些?
A.
网络购物
B.
支付宝
C.
高铁
D.
抖音
E.
拼多多
F.
共享单车
【单选题】What does “turn out” imply?
A.
The reason for doing something.
B.
Something happens in that way or has the result the consequence of something.
C.
The potential risk of doing something.
D.
The original plan of doing something.
【单选题】What's unique about red-black trees compared to AVL trees? 红黑树相比于AVL树的特点是:
A.
The balance factor of each node falls within [-1, 1] 每个节点的平衡因子的绝对值不超过1
B.
It is a balanced binary search tree 是平衡二叉搜索树
C.
The search time is O(lgn) 支持O(lgn)时间的查找
D.
The topology changes no more than O(1) after each insertion/deletion每次插入/删除后拓扑结构的变化不超过O(1)
【单选题】You may choose one or more than one correct answer(s).1. Why is the student coming for the teacher?
A.
He quarreled with his classmates.
B.
He was stressed about the college entrance examination.
C.
He missed several classes due to illness
D.
He was often stressed when he faced an academic problem.
【多选题】好的选题从哪里来?
A.
知己知彼:你对一个领域的了解程度会直接影响你的选题
B.
现实需求:真正来自现实生活的需求最有生命力(洞察力)
C.
长期思考:有的问题需要多年的思考
D.
宽广胸怀:一个人的出发点直接决定了选题可能的高度
E.
好的选题非一日之功
【单选题】下列集合中,有最大值的集合是 ( ).
A.
$ \{x|x\in (0,1),x\in Q\} $
B.
自然数集
C.
有限个数构成的集合$ \{a_1,a_2,\cdots,a_n\} $
D.
$ \{x\in R|x^2-2x-3 < 0\}$
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