根据句意，英文释义，首字母或中文提示写出所缺单词。

1. You shouldn't _________ (惊吓) the little baby.

2. We should be _________ (not rude) to old people.

3. Birds k________ on the cage door with their beaks when they are hungry.

4. My hero is Lu Yi. I think he is very ________ (good-looking).

5. My little brother never tells lies (撒谎). We all think he is _________.

6. Tom won the first prize in the drawing _________ (竞赛).

如图是小龙探究“杠杆平衡条件”的实验装置，B处所挂钩码总重4N，用弹簧测力计在C处拉杠杆保持水平平衡．弹簧测力计的最小读数是（　　）

A．4N

B．6N

C．3N

D．无法确定