因物体的重力和弹性体的压缩、拉伸与扭转等作用产生的转矩是()
A.电磁转矩
B.反抗转矩
C.位能转矩
D.飞轮转矩
参考答案:C
阅读理解。
This is a picture of Mr. Li's family. The man in the middle is Mr. Li. The woman is Mr. Li's wife. They have two sons. The child behind Mr. Li is Li Lei. He's thirteen. The other in front of Mrs. Li is Li Ming. He is eleven. Li Lei and Li Ming are in the same school, but not in the same grade. Li Lei is in Grade Two. Li Ming is in Grade One. They are good students.
1. There are _______ people in the picture.
A. three
B. four
C. five
D. six
2. LiLei and Li Ming ______ in the same grade.
A. is
B. isn't
C. are
D. aren't
3. Mr. and Mrs. Li have _______.
A. one boy, one girl
B. two children
C. two girls
D. one boy
4. Li Ming is ________ brother.
A. Mr. Li's B. Mrs. Li's
C. Li Lei's
D. we don't know.
5. How old are Li Lei and Li Ming? They're _____.
A. eleven and thirteen
B. eleven and twelve
C. twelve and eleven
D. thirteen and eleven
汽车、轴承及自行车的生产一般属于( )。
A.成批生产
B.单件生产
C.大量生产
D.少量生产