选择废石场（排土场）场地的主要原则有那些？

阅读理解。

    It was half-past eight in the morning. The telephone bell rang and Mary went to answer it. It's me-Peter.

Hello, who's that? she asked.

    Peter was a friend of Mary's eight-year-old brother, Johnny.

    Oh hello, Peter. What do you want? said Mary.

    Can I speak to Johnny?

     No, said Mary, you can't speak to him now. He is busy. He is getting ready for school. He is eating his

breakfast. Grandmother is combing his hair. Sister is under the table, putting his shoes on. Mother is getting

his books and putting them in his school bag. Goodbye, I've got to go now. I have to hold the door open.

The school bus is coming.

1.Who went to answer it when the teltphone bell rang? [ ]

A.Johnny's sister

B.Peter

C.Johnny

D.Johnny's mother

2.Whom did Peter want to speak to? [ ]

A.Mary's brother

B.Mary's sister

C.Mary's grandmother

D.Johnny's mother

3.Johnny couldn't speak to Peter because Johnny ______. [ ]

A.was combing his hair

B.was putting his shoes on

C.was getting his books

D.was busy eating his hreakfast

4.How do you say to a stranger who is answering your telephone?[ ]

A.Who are you?

B.Anything to say?

C.Who is it?

D.Please

5.From this story we know that Johnny was _____. [ ]

A.a lazy boy

B.a clever boy

C.a busy boy

D.a hungry boy

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哪个温度加热淬火后马氏体含碳量较多？