在异方差条件下普通最小二乘法具有如下性质（）A.线性 B.无偏性 C.最小方差性 D

如图所示，红蜡块能在玻璃管的水中匀速上升，若红蜡块在A点匀速上升的同时，使玻璃管水平向右做匀加速直线运动，则红蜡块实际运动的轨迹是图中的(    )

A．直线P

B．曲线Q

C．曲线R

D．无法确定

物体做匀速直线运动，有一对大小为25N的平衡力加在这个物体上，该物体的运动状态将______．（改变或不改变）

读写任务 (共1小题,满分25分)

阅读下面的短文，然后按照要求写一篇150词左右的英语短文。

Hi, I am Mike. I just went through my first year of college. The toughest part on me at fir

st was the general adjustment.1 went to a very small high school where my mom was a teacher and she did practically everything for me. But at the college I needed to know some basic life skills. such as balancing a check—book, laundry, and the things you have to be able to handle that I never thought of in the high school! It was really tough for me at first and I got badly homesick.

Once that first semester was over and I got used to the college life, I loved it—good facilities, helpful instructors. and a good library. The Students’ Union organizes various parties every week. I also go to cinemas and concerts, and often spend Saturday nights in pubs and clubs.

One thing I think is important is to get yourself active in things. I was on the dance team in college and met a ton of people that way ··· it was so much easier to make friends when you had a common ground.

[写作内容]

学校最近组织了一次中美学生交流活动，你参加其中的“大学校园生活”讨论。听完Mike的发言之后，你准备写一份发言稿，题目是“Preparing Myself for College Life”，内容要点包括：

1. 以约30个词概括Mike的发言要点；

2. 然后以约120个词谈谈你理想的大学生活，内容包括：

(1) 对中学生活的感受；

(2) 理想的大学生活；

(3) 中学生活和大学生活的差别，以及你打算如何适应。

[写作要求]

1. 在作文中可以使用自己亲身的经历或虚构的故事，也可以参照阅读材料的内容但不得直接引用原文中的句子；

2. 作文中不能出现真实姓名和学校名称。

[评分标准]

概括准确，语言规范，内容合适，篇章连贯。

下列各项人粪尿的无害化处理的措施中，不科学的是（　　）

A．兴建生态厕所

B．高温堆肥

C．建沼气池

D．加水稀释

正常硫酸钡吸附血浆中含有的主要凝血因子为（）

A.因子Ⅰ、Ⅴ、Ⅷ、Ⅺ、Ⅻ

B.因子Ⅸ、Ⅹ、Ⅺ、Ⅻ

C.因子Ⅱ、Ⅶ、Ⅹ

D.因子Ⅶ、Ⅹ

E.因子Ⅺ、Ⅻ