图表示气流通过机翼上下表面时的情况，比较机翼上下a、b两点的流速和压强

A．a点的空气流速大，压强大

B．a点的空气流速大，压强小

C．b点的空气流速大，压强大

D．b点的空气流速大，压强小

A woman tells the nurse that her 6-year-old daughter has severe nosebleeds. Which of the following instructions should the nurse give this woman to manage nosebleeds()

A. Help the child assume a comfortable position with her head tilted backward.

B. Tilt the child’s head backward and place firm pressure on the nose.

C. Help the child lie on her stomach and collect the blood on a clean towel.

D. Place the child in a sitting position with her neck bent forward and apply firm pressure on the nasal septum.