电子酸碱测试仪pH值测量范围（）
A.0～10
B.0～7
C.0～9
D.0～14
参考答案：D
She’ll never forget her stay there ________ she found her son who had gone missing two years before.
A．that
B．which
C．where
D．when
动脉血气分析pH的正常值是（）
A.7.35～7.45
B.6.35～7.45
C.7.4～7.65
D.7.45～7.55
E.6.45～7.45
