题干

下列说法正确的是(   )

A:在化学反应中某元素由化合态变为游离态,该元素一定被还原了

B:失电子难的原子其得电子的能力一定强

C:电子层结构相同的各种离子,它们的半径随核电荷数的增加而减小

D:最外层电子数较少的金属元素,一定比最外层电子数较它多的金属元素活泼

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答案(点此获取答案解析)

C

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A Father and a Son

    Passing through the Atlanta airport one morning, I caught one of those shuttles that take travelers from the main terminals (航站楼) to their boarding gates. Not many people consider them fun, but on this Saturday I heard laughter. At the front of the first shuttle were a man and his son.

    We had just stopped to let off passengers, and the doors were closing again. “Here we go! Hold on to me tight!” the father said. The boy, about five years old, made sounds of happiness.

    “Look out there!” the father said to his son. “See that pilot? I bet he's walking to his plane.” The son turned his neck to look forward.

    As I was early for my flight, I decided to go back to the terminal. Where I went back again, I saw that the man and his son had returned too. I realized then that they hadn't been heading for a flight, but had just been riding the shuttle.

    “I want to ride some more!”

    “More?” the father said, mock-angry but clearly pleased. “ You are not tired?”

    “This is fun!” his son said.

    “All right.” the father replied, when a door opened, we all got on.

    There are parents who can afford to send their children to Europe or Disneyland, and there are parents who live in million-dollar houses and give their children cars and swimming pools, yet something goes wrong.

    “Where are all those people going, Daddy?” the son asked.

    “All over the world,” came the reply.

    The other people in the airport were leaving for far destinations (终点) or arriving at the ends of their journeys. The father and son, though, were just riding this shuttle together, making it exciting, enjoying being together.

    So many troubles in this country. So many questions about what to do. Here was a father who cared about spending the day with his son and who had come up with this plan on a Saturday morning.

    The answer is so simple: parents who care enough to spend time, and to pay attention and to try their best. It doesn't cost a cent, yet it is the most valuable thing in the world.

    The shuttle picked up speed, and the father pointed something out, and the boy laughed again.