题干

下列有关物理知识的说法中正确的是(   )

A:医生用B超查看胎儿的发育情况是利用声传递能量

B:摩擦力总是阻碍物体的运动

C:一个物体由运动变为静止,一定受到了力的作用

D:正在空中快速上升的小球,当它所受的一切外力突然消失,小球将立刻下落

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答案(点此获取答案解析)

C

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    When I look back at my decision to be a working mom, I realize that I didn't think I had any other choice. Hubby and I had been a two-income family 1 the time we were married. It didn't occur to me that we would be anything else though it's hardly news that the choice has its 2.

    Hubby traveled a lot when our kids were young, and I often was a weekday single mom. I had an understanding boss,who allowed me to work a(n) 3 schedule for about 12 years. My 32-hour work week provided the chance to 4 in my kids' kindergarten classrooms.

    The woman who cared for the kids in our 5 was truly a gift from God. Nan and I 6 values and parenting styles.

    Never underestimate (低估) the value of 7. When Dad was away, the kids knew the drill. Though sports activities and piano lessons 8 interrupted our schedules, generally we got up, fed and out without much commotion (混乱) and back in, fed and 9 with a little time left over for a game or a favorite TV show. Mom got a few minutes of 10 before crashing herself (睡觉).

    Looking back on the past, I realize we could have made other 11. We could have been vegetable gardeners. Lots of families 12 on one income. But I think we would have lost something just as important as my 13.

    My work at the News Sentinel has been 14 and exciting. I've worked with people I never would have met had I been at home. I've spent my career 15 sentences and stories and learning and passing along information about our community. My coworkers are my Tennessee family.

    My work has been 16 to me in important ways, and I think it has made me a more interesting and satisfied 17 and parent. And our family has learned to 18 the time we do have together.

    19, if I had to do it over again, I wouldn't change my decision to be a working mom. And I wouldn't change a single thing about the kids who 20 it.