大肠埃希菌H抗原为( )
A．耐热蛋白质B．不耐热蛋白质C．多糖磷脂D．B+CE．以上都不对
参考答案：B
桩的承载力大小主要由（）决定。
A.桩侧土和桩端土的物理力学性质
B.桩的长径比
C.桩的侧表面积
D.桩的成桩效应
The company has a target capital structure of 40 percent debt and 60 percent equity. $1000 par value bonds pay 10 percent coupon (semi-annual payments) , mature in 20 years, and sell for $ 849.54. The company stock beta is 1.2. Risk-free rate is 10 percent, and market risk premium is 5 percent. The company’s marginal tax rate is 40 percent. The weighted average cost of capital (WACC) is closest to:（）
A. 12.5%.
B. 13.0%.
C. 13.5%.
