过滤器运行的主要参数有()。
A、滤速;
B、压差;
C、过滤周期;
D、滤层的截污能力。
参考答案:A, C, D
—Does Bill do his new job well?
— ________ his old job. I’m afraid there’s no hope for him.
A.Not better than
B.No better than
C.Not so well as
D.Not as well as
下列省级行政区中有两个简称的是()
A.河南省
B.湖南省
C.甘肃省
D.山西省