A.topicsB.ideasC.argumentsD.themes
A. topics
B. ideas
C. arguments
D. themes
A.approvedB.admiredC.deridedD.scolded
A. approved
B. admired
C. derided
D. scolded
A.evilB.sinC.wickednessD.bad
A. evil
B. sin
C. wickedness
D. bad
大气含尘浓度≥0.5μm的为3×105粒/L,经三级过滤器,≥0.5μm过滤效率分别为18%,55%,99.9%,则过滤后的空气含尘浓度≥0.5μm为()粒/L。
A. 111
B. 137
C. 152
D. 178