15.某老师在试卷分析中说:参加这次考试的41位同学中,考121分的人数最多,虽然最高的同学获得了满分150分,但是十分遗憾最低的同学仍然只得了56分,其中分数居第21位的同学获得116分.这说明本次考试分数的中位数是( )
| A. | 21 | B. | 103 | C. | 116 | D. | 121 |
14.5的相反数是( )
| A. | 2 | B. | -5 | C. | 5 | D. | $\frac{1}{5}$ |
8.
如图,在Rt△ABC中,∠C=90°,AB=5,AC=4,则sinA的值是( )
0 294605 294613 294619 294623 294629 294631 294635 294641 294643 294649 294655 294659 294661 294665 294671 294673 294679 294683 294685 294689 294691 294695 294697 294699 294700 294701 294703 294704 294705 294707 294709 294713 294715 294719 294721 294725 294731 294733 294739 294743 294745 294749 294755 294761 294763 294769 294773 294775 294781 294785 294791 294799 366461
| A. | $\frac{3}{4}$ | B. | $\frac{3}{5}$ | C. | $\frac{\sqrt{7}}{4}$ | D. | $\frac{4}{5}$ |