下列物质溶于水时，溶液温度明显降低的是[ ]
A．氯化钠
B．硝酸铵
C．浓硫酸
D．氢氧化钠
答案：B
It’s very dangerous to be ____ to the SARS virus without any protection.
A disclosed B uncover C affected D exposed
成形车刀名义后角αf
