慢性呼衰，给氧原则是（）
A.持续高流量
B.持续低流量吸氧
C.间断低流量
D.先高流量待动脉氧饱和度恢复正常改为低流量
E.间断高流量
参考答案：B
An investor gathered the following information about an option-free U. S. corporate bond: Par Value of $10 million Convexity of 45 Duration of 7 If interest rates increase 2 percent (200 basis points), the bond’s percentage price change is closest to:()
A. -14.0%
B. -15.8%
C. -12.2%
