已知在Rt△ABC中，∠C为直角，AC=4cm，BC=3cm，sin∠A=___

阅读短文，完成下面的选择题，把序号填在括号里。

      Hello, I'm Jack. This is my family photo. They are my grandparents, my parents and me. My grandpa is

strong and tall. He's a farmer. He likes sports. My grandma is a housewife (家庭主妇). She likes painting. My

mother is a teacher. She's thirty-two. She likes music. My father is a doctor. He likes music, too. I love my

family!

1. There are _____________ people in my family.

2. My grandma is a _____________.

A. housewife

B. farmer

3. My grandpa likes _____________.

A. sports

B. computer

4. My mother is _____________.

A. 32

B. 33

5. My parents like _____________.

A. painting

B. music

下述降压药中最易引起体位性低血压的是哪一个（）。

A.利舍平（利血平）

B.胍乙啶

C.乌拉地尔

D.吲哒帕胺

E.卡托普利

操作中如何做到不排放不凝气？

在水松纸导纸辊的检查过程中应检查导纸辊表面有无磨损，当直径方向磨损大于（）mm时，需进行更换。

A.0.5～1

B.0.1～0.2

C.0.2～0.4

D.0.3～0.6