隧道是高速公路上的特殊路段也是事故多发路段之一。某日,一货车A因故障恰停在隧道内

题型:计算题

问题:

隧道是高速公路上的特殊路段也是事故多发路段之一。某日,一货车A因故障恰停在隧道内离隧道入口d="50" m的位置。此时另一轿车B正以v0="25" m/s的速度匀速向隧道口驶来,轿车B的驾驶员在进入隧道口时,才发现停在前方的货车A并立即采取制动措施。假设该驾驶员反应时间t="0.6" s,轿车制动时受到的阻力恒为自身重力的0.75倍,取g="10" m/s2

(1)试通过计算说明轿车B是否会与停在前面的货车A相撞?

(2)若会相撞,那么撞前瞬间轿车B速度大小为多少?若不会相撞,那么停止时与货车A的距离为多少?

考点:s-t图像
题型:计算题
阅读下面A-E五段叙述, 并将其与56-60五个主题说明分别匹配.
Reading Tips (suggestions)

A. Have everything ready:
●  something to read
●  marker to highlight(标出) difficult words
●  dictionary
●  your vocabulary book
●  pen to write down the new words
B. Choose a magazine or a book about a subject that you like, because you are going to spend time and
     money on it. You can also read newspapers.
C. Read something that you can, more or less, understand. If you need to stop every three words to look
     in a dictionary, it will not be interesting for you and you will soon feel frustrated.
D. For example, read for a short time once a day. Fifteen minutes every day is better than two hours every
     Sunday. Set time to read and keep to it. For example, you could read for fifteen minutes before you go
     to bed, or when you get up, or at lunchtime.
E. If there  are four or  five new words on a  page, write them in your  vocabulary book. But don't  write
    them while you read. Instead, as you read, try to guess their meanings first. Mark them with a pen and
    then come back for them after you have finished reading. Then you can check in a  dictionary  before
    you add them in your vocabulary book.

(   ) 1. Try to read at the right level(水平)
(   ) 2. Make a note of new vocabulary
(   ) 3. Try to read regularly (often)
(   ) 4. Be organized
(   ) 5. Read what interests you
题型:计算题

简述足的基本结构和类型,以及各类型的特点,并举例其代表类群。

题型:计算题

在Photoshop中进行全景图的拼接时,可以使用图层控制面板上的图层的混合模式,将图层的混合模式改为()以便对准拼接的图像。

A.正常

B.差值

C.排除

D.正片叠底

题型:计算题

关于美甲师喷绘完毕需要注意的事项,下列说法错误的是()。

A、清理工作台

B、在甲油完全干燥后,用桔木棒制作棉签,蘸取洗甲水清理指甲两侧甲沟内和周围皮肤上的喷绘颜料

C、建立顾客档案,预约下一次服务时间

D、在涂甲油前,用桔木棒制作棉签,蘸取洗甲水清理指甲两侧甲沟内和周围皮肤上的喷绘颜料

题型:计算题

使用蓄电池时,随着环境温度下降,蓄电池的容量()。

A.下降

B.升高

C.不变

D.不确定

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