7.如图,数轴上A,B两点所表示的两数的( )
A.和为正数 B.和为负数 C.积为正数 D.积为负数
6.如图,已知圆柱体底面圆的半径为,高为2,AB,CD分别是两底面的直径,AD,BC是母线若一只小虫从A点出发,从侧面爬行到C点,则小虫爬行的最短的路线的长度是
(结果保留根式)
5.如图,身高为1.6cm的某学生想测量一棵大树的高度,她沿着树影BA由B到A走去,当走到C点时,她的影子顶端正好与树的影子顶端重合,测得BC=3.2m,CA=0.8m,则树的高度为 .
4.如图,将Rt⊿ABC绕点A逆时针方向旋转90º,则旋转后B点的坐标是 。
3. ;若点在反比例函数的图象上,则k= ;36º的补角为
2.Sin600= ;分解因式:7x2-63= ;人体中约有2.5×1023个红细胞,则2.5×1023中有 个有效数字。
1.|-3|= ;的相反数为 ;-30= ;
30. I was not angry at all _________ he had done.
A. that B. which C. what D. those
Keys:
1-5. BCBDC 6-10. ACDBA 11-15. CDDAC 16-20. CBBAB
21-25. BDAAB 26-30. ACBBA
29. He must catch the horse. He knew _______ man than he had tried.
A. well B. better C. it better D. best
28. The working hours will be changes from 8 to 12 _______ 7 to 11.
instead of B. to C. from D. and from