题干

下列说法正确的是(   )

A:用手托着重1N的苹果水平移动1m,手对苹果做的功是1J

B:质量为9.8kg的物体在地球表面所受重力大小不等于1N

C:重为1N的苹果放在1m2的水平桌面上,苹果对桌面压强是1Pa

D:某人的心脏每分钟跳动72次,其跳动频率为72Hz

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答案(点此获取答案解析)

B

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完形填空

    When you live in a seasonal environment, you can learn that both outdoor and indoor activities have their place. As the seasons1 so does your mood. Certain activities become more or less attractive2 the weather and the length of the day.

    Spring is a time of the year when the world starts to3 from its winter sleep. During this season, I enjoy going on long walks through parks and watching the world come4.

    Many consider summer to be the top of the year. The city comes into full swing5 the weather becomes warmer and warmer. During the summer, I prefer to spend the daytime anywhere that is air-conditioned. This 6include the library, a shopping center or a movie theater. I often enjoy spending the7evenings sitting on the wide balcony of my house and having drinks with my friends.

    Fall, with the8 of the leaves and the summer heat gradually 9is probably another 10 time to go on long walks during the day. I love to be 11during fall and see the life of the city returning to its hibernation (冬眠). Another12to go outside during autumn is to 13the last days of warmth until the next year.

    Winter14 the shortening of days and cooler weather. Outdoor activities tend to become less 15 and sinking down on the sofa with a good book becomes my16 activity. It is not enjoyable to spend time outside if it is too 17I only choose to go outside when I want to go skiing.

    So, my 18to spend time indoors or outdoors is vastly dependent on the19. Different seasons 20different activities and therefore it is Impossible to choose whether I would spend all of my spare time indoors or outdoors.