有两个力，一个是20N，另一个为5N，他们的合力可能等于（） A．14N B．30N

A client hospitalized with a pneumothorax has the following arterial blood gas (ABG) analysis: pH, 7.19; partial pressure of arterial carbon dioxide (PaCO₂), 63 mmHg; and,22 mEq/L. A chest tube was inserted and oxygen administered at 4 L/min by nasal cannula. One hour after the initiation of treatment, ABG analysis reveals: pH, 7.28; PaCO₂, 52 mmHg; and ,22 mEq/L. This change in ABG analysis indicates（）

A. respiratory alkalosis.

B. impending respiratory arrest.

C. the need for intubation.

D. improved respiratory status.

Time means everything, so I won’t have you _______your time like that.

A．wasted

B．waste

C．to waste

D．wasting

38～40：

某三层端部墙窗洞处立面如题图所示，窗洞宽1.20m，外纵墙上搁置长向板，板底距离上皮0.72m，板上有女儿墙。若外纵墙墙厚370mm(墙面自重标准值为7.78kN/m²)，已知传至+10.72m标高处的荷载设计值为31.3kN/m。采用MU10砖，M5混合砂浆。

若过梁采用砖砌过梁，则其弯曲抗拉及抗剪承载力与（）项数值最为接近。

A．M=7.36kN·m，V=19.54kN

B．M=5.89kN·m，V=16.7kN

C．M=6.85kN·m，V=17.5kN

D．M=9.51kN·m，V=26.5kN

通脉四逆汤2功效与作用

光具有偏振现象，说明光是（）

A.纵波

B.横波

C.电磁波

D.粒子