假如你是李明的母亲，请根据对话内容完成电话留言。(3分)

A: Hello. I’d like to speak to Li Ming.

B: Sorry. He isn’t in right now.

A: Oh. Can I leave a message?

B: Sure, go ahead.

A: This is Zhang Han speaking. Please tell him not to forget to take his camera tomorrow.

B: OK. Zhang Han . I’ll give him the message myself.

A: Thanks. Goodbye.

B: Bye.

某色谱峰的保留时间为45s，峰底宽为3.5s，柱长是2.0m。试计算理论塔板数和塔板高度.