干性咳嗽的常见病因是（）
A.慢性支气管炎
B.支气管扩张症
C.空洞型肺结核
D.肺脓肿
E.肺癌
参考答案：E
Study the following data, calculate the return on equity for 2007 and 2008.
A．
B．2007
C．2008
D．Pre-interest profit margin (EBIT/S)
E．0.3
F．0.15
G．Asset turnover (S/A)
H．2
I．2
J．Leverage multiplier (A/E)
K．2
L．2
M．Tax retention rate (1-t)
N．0.8
O．0.8
P．Interest expense ratio (I/A)
Q．0.06
R．0.06
孢子培养基
