单项选择题
A.1min,150-200mmHg B.2min,150-200mmHg C.3min,200-250mmHg D.4min,200-250mmHg
A.1小时,10-15cmH2O B.2小时,15-20cmH2O C.3小时,20-25cmH2O D.4小时,25-30cmH2O
A.≤80% B.≤85% C.≤90% D.≤93%