佝偻病的最主要病因是A．缺铁 B．缺乏维生素D C．甲状旁腺功能不全 D．缺钙 E．

读等高线地形图，回答：

若要在图示地区修建水库，水库大坝坝址最好选择在（    ）处。

A．A处

B．B处

C．C处

D．D处

按照题目要求作图

（1）在如图1中，画出使轻质杠杆保持平衡的最小的力F的示意图（要求保留作图痕迹）．

（2）用笔画线代替导线，把如图2中的三孔插座及它的保险丝、电灯及控制电灯的开关接到家庭电路上．

（3）如图3所示，是一台电子秤的部分工作原理图，它是以电压表指针的偏转程度来显示所称物体质量的大小，即电压表示数越大，质量越大．虚线框内R为滑动变阻器，R₀为定值电阻．请在虚线框中完成该工作电路图．要求：当滑动触头P在最上端时，称量质量为零，在最下端时达最大称量．

You recently joined as the project manager of ABC Company. The outgoing project manager mentioned that of late, she had been facing several issues with new change requests. The customers were located in the same office and they interacted directly with the project team and, at times, informally asked for some changes in the project's product. If the changes were small, the project team members usually agreed to do the changes. The project manager found it difficult to prioritize activities and ensure that tasks are done as per schedule. The project had 50 team members and there was some discontent amongst them about the work they were supposed to do. What should be your first priority in this project

A) Create a detailed project scope statement.
B) Align the project objectives with the organizational goals.
C) Ensure proper project scope control.
D) Call a meeting of all the project stakeholders to determine and resolve any outstanding issues.

某羧酸衍生物A，其分子式为C₆H₁₂O₂，实验表明A和氢氧化钠溶液共热生成B和C，B和盐酸反应生成有机物D，C在铜催化和加热的条件下氧化为E，其中D、E都不能发生银镜反应．由此判断A的可能的结构有（　　）

A．6种

B．2种

C．4种

D．3种

施工单位应该在下列（）处危险部位设置明显的安全警示标志。

A.施工现场入口处

B.电梯井口

C.脚手架

D.分岔路口

E.十字路口