一列火车有29节车厢,每节车厢装58吨货物,这列火车大约载货物______吨.
29×58≈1800(吨),
答:这列火车大约载货物1800吨.
故答案为:1800.
With so much noise of the traffic, I couldn't________and do my research work.[ ]
A. put down
B. settle down
C. break down
D. take down
干旱草原环境的标型元素是()。
A.Fe++
B.Fe+++
C.Ca++