安全生活离不开化学．下列做法正确的是（ ） A．厨房煤气泄露，迅速开启排风扇 B

What kind of music do you like to _____?[ ]

A. hear

B. heard

C. listen

D. listen to

血液里红细胞或者血红蛋白含量低于正常值会引起[ ]

A．发炎

B．贫血

C．缺钙

D．营养不良

An analyst is estimating the cost of capital for her firm. She has estimated the before-tax costs of the current sources of capital to be 8 percent of debt and 9 percent for equity, If the firm’s marginal tax rate is 40 percent, the costs of debt and equity she could use in her calculation are closest to:()

A. 4.8% for debt and 5.4% for equity.

B. 4.8% for debt and 9.0% for equity.

C. 8.0% for debt and 5.4% for equity.

信息产品可以全部商品化。

关于异常月经的心理问题错误的是

A．情绪障碍可导致月经周期紊乱
B．与GnRH释放有关
C．与工作高度紧张有关
D．中枢神经系统的神经体液因素对子宫血管无影响
E．与环境变迁有关