3.
如图,AB∥EF,CD⊥EF于点D,若∠ABC=40°,则∠BCD=( )
| A. | 140° | B. | 130° | C. | 120° | D. | 110° |
2.一次数学测验中,某小组五位同学的成绩分别是:110,105,90,95,90,则这五个数据的中位数是( )
| A. | 90 | B. | 95 | C. | 100 | D. | 105 |
19.
如图,△ABC的顶点是正方形网格的格点,则sinA的值为( )
| A. | $\frac{1}{2}$ | B. | $\frac{\sqrt{5}}{5}$ | C. | $\frac{\sqrt{10}}{10}$ | D. | $\frac{2\sqrt{5}}{5}$ |
18.不等式组$\left\{\begin{array}{l}{2x-1≤1}\\{-\frac{1}{2}x<1}\end{array}\right.$的整数解的个数为( )
| A. | 0个 | B. | 2个 | C. | 3个 | D. | 无数个 |
17.
一个几何体的三视图如图所示,则这个几何体是( )
| A. | 球体 | B. | 圆锥 | C. | 棱柱 | D. | 圆柱 |
16.-8的立方根是( )
0 283976 283984 283990 283994 284000 284002 284006 284012 284014 284020 284026 284030 284032 284036 284042 284044 284050 284054 284056 284060 284062 284066 284068 284070 284071 284072 284074 284075 284076 284078 284080 284084 284086 284090 284092 284096 284102 284104 284110 284114 284116 284120 284126 284132 284134 284140 284144 284146 284152 284156 284162 284170 366461
| A. | 2 | B. | -2 | C. | ±2 | D. | -$\root{3}{2}$ |