题目

I don't really know the fact, so I can't (评论) on hisaction. 答案：【1】comment地球上陆地的面积约为149000000km2，数149000000用科学记数法可表示为（　　）A. 1.49×108 B. 1.49×109 C. 14.9×108 D. 14.9×109