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参考答案：
参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】第二篇 Pushbike Peril Low speed bicycle crashes can badly injure—or even kill—children if they fall onto the ends of the handlebars (车把). So a team of engineers is redesigning the humble h...
A.
it is not easy to persuade manufacturers to adopt the new design.
B.
the team of engineers has not found any countermeasures.
C.
children like to ride bicycles at a very low speed.
D.
a lot of children were killed in bicycle accidents in the past 30 years.
【单选题】(2005年)要用冲床在厚度为t的钢板上冲出一圆孔，则冲力大小( )。
A.
与圆孔直径的平方成正比
B.
与圆孔直径的平方根成正比
C.
与圆孔直径成正比
D.
与圆孔直径的三次方成正比
【单选题】要用冲床在厚度为t的钢板上冲出一圆孔，则冲力大小 ( )。
A.
与圆孔直径的平方成正比
B.
与圆孔直径的平方根成正比
C.
与圆孔直径成正比
D.
与圆孔直径的三次方成正比
【单选题】Pushbike er Low speed bicycle crashes can badly injure—or even kill—children if they fall onto the ends of the handlebars (车把). So a team of engineers is redesigning it to make it safer. Kristy A...
A.
Thirty.
B.
Ninety.
C.
50 percent.
D.
More than a third.
相关题目：
【单选题】第二篇 Pushbike Peril Low speed bicycle crashes can badly injure—or even kill—children if they fall onto the ends of the handlebars (车把). So a team of engineers is redesigning the humble h...
A.
it is not easy to persuade manufacturers to adopt the new design.
B.
the team of engineers has not found any countermeasures.
C.
children like to ride bicycles at a very low speed.
D.
a lot of children were killed in bicycle accidents in the past 30 years.
【单选题】以下哪些是裁判员的职责？
A.
因外界干扰停止、推迟或中止比赛。
B.
记录比赛时间和比赛成绩。
C.
执行竞赛规则。
D.
以上答案都正确。
【单选题】(2005年)要用冲床在厚度为t的钢板上冲出一圆孔，则冲力大小( )。
A.
与圆孔直径的平方成正比
B.
与圆孔直径的平方根成正比
C.
与圆孔直径成正比
D.
与圆孔直径的三次方成正比
【判断题】逆旋发球的特点是前冲力强,弧线长,对方接发球时容易借力,但容易漏球。
A.
正确
B.
错误
【单选题】要用冲床在厚度为t的钢板上冲出一圆孔，则冲力大小 ( )。
A.
与圆孔直径的平方成正比
B.
与圆孔直径的平方根成正比
C.
与圆孔直径成正比
D.
与圆孔直径的三次方成正比
【单选题】气井试井时，加重杆重量必须大于气体上升冲力，对于（）的气井，应加大重量。
A.
产水量大
B.
产气量大
C.
产水量小
D.
产气量小
【单选题】提出冲力说的人是（）
A.
毕达哥拉斯
B.
阿基米德
C.
欧几里得
D.
斐劳波诺斯
【单选题】胶印机机械运动的冲力除印刷压力外,主要来自()。
A.
滚筒离让
B.
水、墨辊传动
C.
递纸装置的往复
D.
递纸牙往复摆动和滚筒叼牙开闭
【判断题】足球助理裁判员的旗示有5种。
A.
正确
B.
错误
【单选题】Pushbike er Low speed bicycle crashes can badly injure—or even kill—children if they fall onto the ends of the handlebars (车把). So a team of engineers is redesigning it to make it safer. Kristy A...
A.
Thirty.
B.
Ninety.
C.
50 percent.
D.
More than a third.
【判断题】唯名论者提出的冲力学说试图维护亚里士多德学说的各种界限。()
A.
正确
B.
错误