小型建筑设备监控系统的实时数据库点数为（）及以下。
A.999
B.1200
C.1500
D.2000
参考答案：A
He _____ still here till now when he was born in the city.[ ]
A. stayed
B. stays
C. was
D. was like
适合用做O/W型乳化剂的表面活性剂的HLB值宜在（）
A.3～8
B.8～16
C.7～9
D.13～18
E.18～20
