我国大气污染的类型属于（）
A.煤炭型污染
B.石油型
C.粉尘型
D.SO2污染型
参考答案：A
(2014·枣庄模拟)—He should have been warned of the danger.
—________，but he wouldn’t listen to me.
A．So he had
B．So had he
C．So was he
D．So he was
若长度分别为3cm，7cm，xcm的三根木棒能围成一个三角形，则x的取值范围是______．
