It is the duty of the police to_____social order.( )
A:save
B:reserve
C:preserve
D:rescue
1)2P+5CuSO4+8H2O═5Cu+2H3PO4+5H2SO4
2)11P+15CuSO4+24H2O═5Cu3P+6H3PO4+15H2SO4
下列有关说法中错误的是( )
“有一个大洲,那里有世界上最广阔的热带雨林区,有世界上最长的山脉,有世界上最大的高原” 该大洲是 ( )