下列属于气开形式的是（）
A.气压信号增加，阀关小
B.气压信号减小，阀开大
C.气压信号增加，阀开大
D.气压信号减小，阀关小
参考答案：A, B
_____ into use in April 2000, the hotline was meant for residents reporting water and heating supply breakdowns.
A．Put
B．Putting
C．Having put
D．Being put
根据MCV、RDW的贫血形态学分类，缺铁性贫血属于（）。
A.小细胞均一性贫血
B.小细胞非均一性贫血
C.正常细胞均一性贫血
D.大细胞均一性贫血
E.大细胞非均一性贫血
