题干

一个质点做方向不变的直线运动,加速度的方向始终与速度方向相同,但加速度的大小逐渐减小到零,则在此过程中(   )

A:速度逐渐减小,当加速度减小为零时,速度达到最小值

B:速度逐渐增加,当加速度减小为零时,速度达到最大值

C:位移逐渐增大,当加速度减小为零时,位移不再继续增大

D:位移逐渐减小,当加速度减小为零时,位移不再继续减小

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答案(点此获取答案解析)

B

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    Reaching Out to a New Friend in Starbucks

    I'm a single mom looking for a job.One morning I had grabbed my favorite spot at a local Starbucks and was going through the newspaper when I noticed a man in ragged clothing looking really untidy.I felt led to speak to this man and so I did.

    I learned that he was homeless and just wandered from place to place.Starbucks was nice enough to allow him to come in from the cold or the heat depending on the day.I also learned that he used to be an architect,but as we spoke I saw more and more that he wasn't at the fullest of mental capabilities,which made me even more upset that he didn't have a place to go.

    I sat with this man for a very long time in Starbucks calling different clinics,hospitals,shelters,police departments.He even gave me a beat up business card of a gentleman saying that was his son's phone number.It was an out-of-state number,but I called anyway but was not able to reach him.Unfortunately,all the places I called were unable to take him.

    I asked him if he was hungry and he said yes,so I went down the street to a deli(熟食店)and ordered a sandwich and drink.When I got back,my new-found friend became angry for a reason I was not aware of or maybe it was some sort of mental disturbance.All I could do was set the sandwich down and told him that I'll leave it there for him if he wanted it and I left.I walked around town for a couple of minutes and then headed back to see if he was still there.

    A man who was sitting in Starbucks most of the time when I was there came out and told me that the man ate the sandwich and that he was touched that I had sat with him like I did.It seems to me that no matter whether something goes awry(非正常的)on the surface,there is always something beautiful at a deeper level.

    I still remember my friend.I looked for him every time I was in town,but that was the last time I saw him.I hope that I had provided some glimmer of hope that he was not forgotten.