A:2
B:2
C:-2
D:±2
ORDER FORM
Address: 12 Heping Street
Phone number: 628—2865
Order:
Dumplings: 12 beef and carrot dumplings
Soup: one tomato soup
Drinks: One large green tea and two small orange juices
一个棱长都为a的直三棱柱的六个顶点全部在同一个球面上,则该球的表面积为( )
读“地球上的水循环图”,完成下列问题.
化简(1a+1b)÷1ab的结果是( )