题干

下列有关合金性质的说法正确的是

A:合金与各成分金属相比较,具有许多优良的物理、化学或机械性能

B:相同金属元素形成的合金,元素的含量有可能不同,但其性能是相同的

C:镁铝合金在盐酸中不能完全溶解

D:合金具有各成分金属性质之和

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答案(点此获取答案解析)

A

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    Last April, on a Sunday, we took one of our “nowhere” drives. My husband was quietly driving along a back road. I was occupied in the front passenger seat watching the scenery.

    I noticed out of the corner of my eye that my husband was struggling to look out of my window. This frightened me, since his eyes should be on the road in front of him. I asked him what he was looking at out of the windows, and he quietly replied, “Nothing.”

    After a few minutes, I looked over at my husband and noticed a tear running down his cheek. I asked him what was wrong. This time he told me, “I was just thinking about Pop and a story he had once told me.” It had something to do with Pop, his friend from childhood, and I wanted to know the story, so I asked him to share it with me.

    He said, “When I was 8 years old, Pop and I were out fishing and he told me that the pine trees know when it is Easter.”

    I have no idea what he meant by that, so I pressed him for more information.

    He continued on… “The pine trees start their new growth in the weeks before Easter because spring is drawing near. If you look at the tops of the pine trees, you will see the yellow shoots. As the days get closer to Easter Sunday, the tallest shoot will branch off and form a cross. By the time Easter Sunday comes around, you will see that most of the pine trees will have small yellow crosses on all of the tallest shoots.”

    I turned to look out of the window and I couldn't believe my eyes. It was a week before Easter, and you could see all of the trees with the tall yellow shoots stretching to the sky.

    The tallest ones shone in the sunlight like rows of tiny golden crosses. May you find your Easter season filled with beautiful golden crosses!