隧道防火涂层应达到设计要求厚度，测点厚度值副偏差不得大于（）mm，厚度不足部分的连续

如图所示，平行板电容器的两极板A、B接于电池两极，一带正电的小球悬挂在电容器内部，闭合S，电容器充电，这时悬线偏离竖直方向的夹角为θ，以下分析正确的是（   ）

A．保持S闭合，将A板向B板靠近，则θ增大

B．保持S闭合，将A板向上平移一小段距离，则θ变小

C．断开S，将A板向上平移一小段距离，则θ变小

D．断开S，将A板向B板靠近，则θ变大

下列关于债券利率风险的说法，不正确的是( )。

A．也叫价格风险

B．当利率上涨时，债券价格上涨

C．对于在到期日前转让债券的投资者来说，利率上涨会减少投资人的资产收益

D．债券的到期时间越长，价格风险越大

用所给词的适当形式填空。

1. The film is very _____ (surprise) and I'm( surprise) at it．

2. She _____ (buy) some flowers for her mother yesterday.

3. While I was _____ (shop), I saw my best friend.

4. The train usually _____ (leave) the station at ten o'clock in the morning.

5. I _____ (shop) in a supermarket when you called me up.

6. It's _____ (usual) for the trees to flower so early.

7. How about _____ (go) for a drive?

8. Listen! Someone _____ (knock) at the door.

9. What _____ you _____ (do) at 9:00 am. yesterday?

10. I _____ (wait) for the bus this time yesterday.

把一个圆沿对称轴分成两个半圆后，周长增加了12厘米．每个半圆的周长是______厘米．

自总皂苷中分离甾体皂苷可选用

A．乙醚沉淀法
B．胆甾醇沉淀法
C．铅盐沉淀法
D．吉拉尔试剂提取法
E．碱水提取法