使用单位应建立压力管道（）制度。
参考答案：巡回检查和日常维护保养
Was it ______ he was playing volleyball on the playground_________ he got hurt?
A．that; when
B．when; that
C．that; where
D．where; that
pH=7.22，PaCO=54mmHg，BE=-5.0mmol/L（）
A.碱血症
B.代谢性酸中毒
C.呼吸性酸中毒
D.代谢性碱中毒
E.呼吸性碱中毒
