结合上下文及所给首字母填空。

     This i______ (1) a classroom.  It is nice a______(2) bright, but it is

s______ (3). The doors and w______(4) are clean. The desks and chairs

are clean, t______(5).  The walls are white. O______(6) the front wall

there is a b______(72).  The teacher's desk is near it.  On the desk there

are s______(8) flowers and pencils. There is a clock on the wall. It's not

old. It is n______(9).  Now there are o______(10) eight students in the

room. They are cleaning the classroom.

一患者的动脉血气分析示：pH7.20，HCO₃^-20mol/L，PaCO₂50mmHg，PaO₂45mmHg。

可能的酸碱失衡诊断为（）。

A.呼吸性酸中毒

B.呼吸性碱中毒

C.呼吸性酸中毒并代谢性酸中毒

D.呼吸性酸中毒并代谢性碱中毒

E.代谢性酸中毒