根据情景. 填入恰当的句子补全对话。

A:What beautiful shells! Are they yours?

B:Yes, they are.

A:1.                          

B:When I was six years old.

A:2.                                

B:For eight hours.

A:3.                            

B:About 200.

A:Wow! So many!  4.                                    

B:The one that looks like a dog. I like it best. It's very beautiful. And my uncle gave it to me for my

   birthday.

A:Can I have a look?

B:5.             . Here you are.

电感耦合等离子体原子发射光谱法测定环境空气总悬浮颗粒物中金属和非金属时，用滤膜采集颗粒物样品后进行样品制备，砷和铅元素样品的制备方法相同。