空肠弯曲菌的分离培养条件中对氧的浓度一般为（）。 A.5％～10％ B.2％ C.2

阅读对话，回答问题。

A: Excuse me, who's that man, Xiaohua?    

B: He's my father.

A: Is that woman your mother?            

B: No, she isn't. She's my aunt, Miss Liu.

A: Where's your Mum?                  

B: Look! She's in the car.

A: Oh,I see.   

1. Where's Xiaohua's Mum?

2. Who's that man?

3. Is Miss Liu Xiaohua's Mum?

雨后泰山飞流湍急，请你结合图片中泰山瀑布的景象提出三个物理问题。

问题一：_________________________________________；

问题二：_________________________________________；

问题三：_________________________________________。

单项选择。

— ______ five donuts?

— Five yuan. [ ]

A. How many for

B. How much for

C. How much is

D. How tall is

企业经营亏损必然对应着现金短缺。

有（）种致病因子可通过血液传播。

A.10

B.20

C.25

D.30

E.35