焦炉压力需要测定的有()
A.蓄顶吸力
B.看火孔压力
C.集气管压力
D.煤气压力
参考答案:A, B, C
时钟在3点时打3下用了6秒钟,9点钟时打9下要用几秒钟?
Koalas sleep the day and night they get up and eat leaves. [ ]
A in;in
B. at;in
C. at; at
D. during; at