A：长春
B：沈阳
C：锦州
D：营口
NA为阿伏伽德罗常数的值．下列说法正确的是（ ）
-You look so worried, what’s wrong?
-More and more people like me begin to worry about the ______ pollution after the haze (雾霾) appeared in Beijing and some other cities in China.
一辆汽车停在水平地面上，一个人用力水平推车，但车仍然静止，下列说法中正确的是（ ）
