分析和说明变压器一次侧接通电源后，二次侧没有电压输出的原因。

阅读短文，选择正确答案。

      Hello! I'm Sam. It's my birthday. I'm nine. Here are my birthday presents. How many gifts? Look! Two

pens, three pencils, a bag, a cake, and a doll panda. Look! This is her head. It's white. This is her leg. It's black.

What's that? Is that a bird? No, it isn't. It's a duck. Look, this is his body. It's blue. That is his head. It's red.

And his foot is yellow.

1. It's _____________ birthday.

A. Tom's

B. Sam's

C. Mike's

2. Sam is _____________.

A. eight

B. nine

C. ten

3. How many gifts in all (总共)? 

A. Eight.

B. Nine.

C. Ten.

4. This is the doll panda. Her leg is _____________.

A. black

B. white

C. yellow

5. That is a duck. His body is _____________.

A. red

B. blue

C. green

省、自治区、直辖市(食品)药品监督管理部门对提供虚假的证明文件、申报资料、样品或者采取其他欺骗手段申请批准证明文件的处理为()

A．不予受理该申请

B．对申请人给予警告，1年内不受理其申请

C．已取得批准证明文件的，撤销其批准证明文件，5年内不受理其申请

D．并处1万元以上3万元以下罚款

E．情节严重的，给予行政处罚

拟胆碱药有：

A．毒扁豆碱

B．匹罗卡品

C．筒箭毒碱

D．哌仑西平

E．新斯的明

用下列装置进行的实验，不能达到相应实验目的的是

A．装置甲：吸收尾气HCl

B．装置乙：制取金属锰

C．装置丙：洗气除去CO₂中的SO₂

D．装置丁：实验室制取NH₃

判断水质是否受人畜粪便污染的最重要指标是

A．细菌总数

B．大肠菌群

C．粪大肠菌群

D．肠道致病菌

E．厌氧芽胞菌