12.下面各数中,( )是自然数.
| A. | -9 | B. | 0 | C. | 2.5 | D. | $\frac{1}{3}$ |
8.
根据甲、乙两车的行程图填空.
(1)甲车每小时行驶54千米.
(2)甲、乙两车速度的最简整数比是6:5.
(3)甲、乙两车8:00从同一地点出发,同向而行$\frac{2}{3}$时后,两车相距6千米.
0 156694 156702 156708 156712 156718 156720 156724 156730 156732 156738 156744 156748 156750 156754 156760 156762 156768 156772 156774 156778 156780 156784 156786 156788 156789 156790 156792 156793 156794 156796 156798 156802 156804 156808 156810 156814 156820 156822 156828 156832 156834 156838 156844 156850 156852 156858 156862 156864 156870 156874 156880 156888 199269
(1)甲车每小时行驶54千米.
(2)甲、乙两车速度的最简整数比是6:5.
(3)甲、乙两车8:00从同一地点出发,同向而行$\frac{2}{3}$时后,两车相距6千米.