圆柱体的体积比圆锥体的体积大2倍．______．（判断对错）
等底等高的圆柱的体积比圆锥的体积大2倍，所以原题说法错误，
故答案为：错误．
下列因素中，与急性胰腺炎发病最密切的是（）
A.胆道疾病
B.饮酒
C.十二指肠液反流
D.外伤
E.医源性损伤
An analyst is doing research about survivorship bias and its impact on measurement ratios. With a failure to comply with performance presentation standard, hedge fund databases and indexes, which are most likely to overstate:（）
A. Sharpe ratios.
B. standard deviation of retums.
C. correlations with returns from common stocks.
