13.下面是小林做的4道作业题:(1)2ab+3ab=5ab;(2)2ab-3ab=-1;(3)2ab•3ab=6ab;(4)2ab÷3ab=$\frac{2}{3}$.做对一题得2分,则他共得到( )
| A. | 2分 | B. | 4分 | C. | 6分 | D. | 8分 |
11.某网站数据显示,2015年第一季度我国彩电销量为1233万台,将1233万用科学记数法可表示为( )
0 295739 295747 295753 295757 295763 295765 295769 295775 295777 295783 295789 295793 295795 295799 295805 295807 295813 295817 295819 295823 295825 295829 295831 295833 295834 295835 295837 295838 295839 295841 295843 295847 295849 295853 295855 295859 295865 295867 295873 295877 295879 295883 295889 295895 295897 295903 295907 295909 295915 295919 295925 295933 366461
| A. | 12.33×105 | B. | 1.233×103 | C. | 0.1233×108 | D. | 1.233×107 |