简述太沙基有效应力原理。
参考答案：
(1)土的有效应力等于总应力减去孔隙水压力。
(2)土的有效应力控制了土的变形。
地球自转的周期是（ ）
①24小时 ②一天 ③一年 ④365天
A．①②
B．③④
C．①③
D．①④
A client is being admitted to the labor unit. Because she's well advanced in labor, the nurse must prioritize the admission questions. Which information is most important to obtain when birth is imminent
A．Duration of previous labor.
B．Frequency of contractions.
C．Presence of bloody show.
D．Expected due date.
