13.在学校组织的实践活动中,小新同学用纸板制作了一个圆锥模型,它的底面半径为1,高为2$\sqrt{2}$,则这个圆锥的侧面积是( )
| A. | 4π | B. | 3π | C. | 2$\sqrt{2}$π | D. | 2π |
12.已知二次函数y=ax2+bx+c中,函数y与自变量x的部分对应值如表:
则当y>2时,x的取值范围是x<1或x>3.
| x | … | -1 | 0 | 1 | 2 | 3 | … |
| y | … | 10 | 5 | 2 | 1 | 2 | … |
11.
如图,在△ABC中,CE是角平分线,∠ACB=90°,若∠A=35°,则∠CEB的度数为( )
0 288696 288704 288710 288714 288720 288722 288726 288732 288734 288740 288746 288750 288752 288756 288762 288764 288770 288774 288776 288780 288782 288786 288788 288790 288791 288792 288794 288795 288796 288798 288800 288804 288806 288810 288812 288816 288822 288824 288830 288834 288836 288840 288846 288852 288854 288860 288864 288866 288872 288876 288882 288890 366461
| A. | 70° | B. | 75° | C. | 80° | D. | 90° |