The nurse is caring for four clients on a step-down intensive care unit. The client at the highest risk for developing nosocomial pneumonia is the one who

A. has a respiratory infection.
B. is intubated and on a ventilator.
C. has pleural chest tubes.
D. is receiving feedings through a jejunostomy tub

对可逆反应4NH₃(g)+ 5O₂(g)4NO(g)+ 6H₂O(g)，下列叙述正确的是

A．达到化学平衡时，υ_正＝υ_逆＝0

B．若单位时间内生成x mol NO的同时，消耗x mol NH₃ ，则反应达到平衡状态

C．达到化学平衡时，若增大容器体积，则正反应速率减少，逆反应速率增大

D．达到化学反应平衡后，改变条件当υ_正＞υ_逆，平衡向正反应方向移动