3.010×105的有效数字是[ ]
A.3,1
B.3,0,1
C.3,0,1,0
D.3,0,1,0,0,0
答案:C
Before shipment, the buyer must send the seller shipping instructions for packing, shipping marks and means of transportation.
减压塔形状特点()。
A.顶部塔径小
B.中间塔径粗
C.底部塔径最粗
D.底部塔径小