the position of the highest point P we first ask ourselves the question from equation number four: 0 when is the velocity in the y direction zero?

为了找到最高点P的所在,我们首先得,解答我们刚才提出的问题：,究竟何时y方向上的速度减为？

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Now, I would think that it is reasonable to ask the following question: What is the average velocity, for instance, between time zero and time four?

现在，我认为,提出如下问题,是十分合理的：,比如说，平均速度是多少，在0到4秒之间？

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By the time he passed four thousand feet he had reached terminal velocity, the wind was a solid beating wall of sound against which he could move no faster.

他穿越四千英尺的高度时，已经达到极速，呼啸着的海风就像一堵坚实的墙，拦在前面，使他无法以更快的速度前进。

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The average two-wheel-drive car carries four such parts, known as constant-velocity joint (CVJ) halfshafts.

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Looj uses a high-velocity, four-stage auger to blast away leaves, dirt and clogs while brushing gutters clean.

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Mr. Appleton, who leaves his wife, Dalynn, and four children, credited his love of high-velocity sporting with helping him make snap business decisions.

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