地球上七大洲的总面积约为149480000km2,用科学记数法表示为____ km2.(精确到10000000)
Apples are my favourite ______.
I'm not sure how much scholarship you will receive, but it will roughly __________your major expenses.
数学游戏题
如图是一个三阶幻方,有9个数字构成,并且每横行,竖行和对角线上的3个数字的和都相等,试填出空格中的数.
14
﹣2
9
16