标准情况下温度是指在（）℃时情况。
A、20
B、0
C、10
D、–4
参考答案：B
当
最小值是( )．
Which of the following are the two most important tools available to the Federal Reserve（）
A. Changing the discount rate and changing bank reserve requirements.
B. Open market operations and changing bank reserve requirements.
C. Changing the discount rate and open market operations.
最小值是( )．