下列符号中，能表示两个氧分子的是 [ ] A．2O2- B．2O C．2O2 D

新华农场第一天收割麦田10.5公顷，第二天比第一天多收割40%，两天一共收割多少公顷？

男性，52岁，患慢性骨髓炎6个月，血红蛋白75g／L，白细胞、血小板正常。血清铁6．23μmol／L，铁蛋白200μg／L，骨髓增生活跃，细胞外铁（++）

该病的发病机制描述不正确的是（）

A.机体造血储备能力降低

B.红细胞生成素相对不足

C.单核-巨噬细胞释放内铁障碍

D.红细胞干细胞凋亡过早

E.细胞利用铁障碍

工程项目( )是指在整个项目的实施阶段开展管理活动，力求使项目在满足质量和进度要求的前提下，实现项目实际投资不超过计划投资。

A．质量控制

B．进度控制

C．造价控制

D．投资控制

某大学一寝室中住着若干个学生。其中，一个是哈尔滨，两个是北方人，一个是广东人，两个在法律系，三个是进修生。该寝室中恰好住了8个人。
如果题干中关于身份的介绍涉及了寝室中所有的人，则以下各项关于该寝室的断定都不与题干矛盾，除了

A．该校法律系每年都招收进修生。

B．该校法律系从未招收过进修生。

C．来自广东的室友在法律系就读。

D．来自哈尔滨的室友在财政金融系就读。

E．该室的三个进修生都是南方人。

The United States is well known for its network of major highways designed to help a driver get from one place to another in the shortest possible time.Although these wide modem roads are generally (1) and well maintained, with few sharp curves and straight sections, a direct route is not always the most (2) one. Large highways often pass (3) scenic areas and interesting small towns. Furthermore, these highways generally (4) large urban centers, which means that they become crowded with heavy traffic during rush hours, (5) the" fast, direct" route becomes a very slow route.However,there is almost always another route to take if you are not in a hurry. Not far from the (6) new" superhighways", there are often older, (7) heavily traveled roads which go through the countrvside. (8) of these are good two-lane roads ; others are uneven roads curving through the country. These secondary routes may go up steep slopes, along high cliffs, or down frightening hillside to towns (9) in deep valleys. Through these less direct routes, longer and slower, they generally go to places (10) the air is clean and scenery is beautiful, and the driver may have a chance to get a fresh, clean view of the world.

第（4）空应选择（）

A．lead

B．connect

C．collect

D．communicate