1.下列四个实数中最大的是( )
| A. | -5 | B. | 0 | C. | $\root{3}{27}$ | D. | $\sqrt{16}$ |
20.在△ABC中,∠C=90°,AB=5,BC=3,则sinB的值是( )
| A. | $\frac{3}{4}$ | B. | $\frac{4}{3}$ | C. | $\frac{3}{5}$ | D. | $\frac{4}{5}$ |
16.把一张圆纸片按如图所示方式折叠两次后展开,图中的虚线表示折痕,则弧AB的度数是( )

| A. | 120° | B. | 135° | C. | 150° | D. | 165° |
13.已知4辆板车和5辆卡车一次共运31吨货,10辆板车和3辆卡车一次能运的货相当,如果设每辆板车每次可运x吨货,每辆卡车每次运y吨货,则可列方程组( )
0 291686 291694 291700 291704 291710 291712 291716 291722 291724 291730 291736 291740 291742 291746 291752 291754 291760 291764 291766 291770 291772 291776 291778 291780 291781 291782 291784 291785 291786 291788 291790 291794 291796 291800 291802 291806 291812 291814 291820 291824 291826 291830 291836 291842 291844 291850 291854 291856 291862 291866 291872 291880 366461
| A. | $\left\{\begin{array}{l}{10x+5y=31}\\{4x=3y}\end{array}\right.$ | B. | $\left\{\begin{array}{l}{4x+5y=31}\\{10x-3y=0}\end{array}\right.$ | ||
| C. | $\left\{\begin{array}{l}{4x=5y}\\{10x+3y=31}\end{array}\right.$ | D. | $\left\{\begin{array}{l}{4x+31=5y}\\{10x=3y}\end{array}\right.$ |