社会系统学派大师巴纳德认为，社会得以正常运转的前提条件是（）
A.协作
B.决策
C.权变
D.能率
参考答案：A
一肝癌患者，突然右上腹疼痛一天，腹腔积液迅速增加，伴心悸、头晕。BP 80/60mmHg，急抽腹水检查为血性腹水。首先考虑哪种情况
A．肝癌合并细菌性腹膜炎B．肝功能不全引起腹水C．癌性腹膜炎D．肝癌结节破裂出血E．急性心功能不全
The following information relates to the distribution of monthly returns from a diversified investment portfolio:
The distribution of monthly returns is best described as:()
A. positively skewed with a long tail on the left side.
B. negatively skewed with a long tail on the left side.
C. positively skewed with a tong tail on the right side.
