预防性用药应当在发生艾滋病病毒职业暴露后多久应用最好（）A、72小时内 B、36小时

我国在南极地区的两个科学考察站——长城站和中山站建设时间选在2月份的主要原因

是（   ）

A．是暖季，气温高

B．是暖季，降水多

C．是冬季，气温高

D．是冬季，降水多

（10分）某同学利用透明直尺和光电计时器来验证机械能守恒定律，实验的简易示意图如图甲所示，当有不透光物体从光电门间通过时，光电计时器就可以显示物体的挡光时间。光电门传感器可测的最短时间为0.01ms。将挡光效果较好的黑色磁带（宽度为d）贴在透明直尺上，从一定高度由静止释放，并使其竖直通过光电门。某同学测得各段黑色磁带通过光电门的时间△t_i与图中所示的高度差△h_i，并将部分数据进行了处理，结果如下表所示。（取g＝9.8 m/s²，注：表格中M为直尺质量）

次数	ti（10-3s）	(m·s-1)		hi（m）	Mghi
1	1.56	2.85
2	1.46	3.05	0.59M	0.06	0.59M
3	1.37	3.25	1.22M	0.13	1.23M
4	1.30	3.42	1.79M	0.18	1.80 M
5	1.25	3.55	2.25M	0.23	2.26M

（1）从表格中数据可知，直尺上磁带通过光电门的瞬时速度是利用求出的，请你简要分析该同学这样做的理由是：                                   。

（2）该同学用20等分的游标卡尺测量出黑色磁带的宽度，其示数如图乙所示，则d =_______mm。

（3）根据该实验表格数据，请在答题纸上绘出图像，由图像可得出结论：                   

It was time for Mr. Rocco to shut up shop when I hurried into the florist’s. “Now, what is it you want?” Mr. Rocco turned to me. “I want the most beautiful flower you have.” I replied. “And just how much do you have to pay for this most beautiful flower?” I held out a wet hand showing a quarter and dime. He nodded, and then showed me a plant on the counter. “I can give you this one for 35 cents.” he said. “Aw, gee,” I protested, “it looks like a weed!” About 18 inches high, the plant was in a small pot covered with faded red paper. “Now trust me, boy—I promise that tomorrow morning when you get up, you will find your most beautiful flower.” said Mr. Rocco. I knew him to be a good honest man, so I agreed to take it.

It was almost midnight when I arrived home. Mom was seriously sick and using the front bedroom. I looked in to see if she was asleep, and then quietly tiptoed in and set the plant on the table beside her bed. I wanted her to be surprised when she woke on Mother’s Day.

The next morning, I dressed and hurried downstairs. The sun was shining through kitchen window as I looked into Mom’s room. She motioned for me to come in, then glanced over at the table where the plant was. Holy mackerel! There were three big yellow trumpet-shaped（喇叭状的）blooms. It was just like Mr. Rocco said—the most beautiful flower I ever saw! When I looked at Mom, she was smiling as tears streamed down her cheeks. She held out her hand for me to come near, then pulled me close and hugged till it hurt. Then, remembering her contagious condition and that she wasn’t supposed to touch me, she quickly let me go.

My dear mom died the next night. The moment she hugged me turned out to be the most wonderful moment of my life. Not only had that beautiful plant helped show just how much I loved her, but I’d always know how much she loved me.

小题1:   The author didn’t like the plant recommended by Mr. Rocco at first because ______.

A．the packing of the plant was shabby

B．the plant was more a weed than a flower

C．the plant appeared too ordinary to be the most beautiful

D．he thought Mr. Rocco was reluctant to do the deal with him小题2:   Mother’s condition was contagious (Line 6, Para.3) for ______.

A．she was at the death’s door

B．she suffered from the illness

C．others were sick of her appearance

D．virus might spread from her to others小题3: When mother hugged the author tightly, she was showing that ______.

A．she liked being given gifts

B．she valued what the author had done for her

C．she was aware of the approaching of death

D．she was touched by the beauty of the flower小题4: The story is mainly developed by______________.

A．time

B．logic

C．comparison

D．cause and result小题5:Which may be the best title of the passage?

A．Flowers of Love

B．A Son’s Love for Mother

C．Low Price, High Value

D．A Special Mother’s Day

过敏性紫癜可分为以下几型

A．紫癜型

B．腹型

C．关节型

D．肠型

E．肾型

病人在全身麻醉后肺通气的改变是（）。

A.控制呼吸时两肺相等

B.自主呼吸时下肺好于上肺

C.自主呼吸时两肺相等

D.控制呼吸时下肺好于上肺

E.自主呼吸和控制呼吸时都是上肺好于下肺