在特定的时间，按协议价格和数量买卖某种指定金融资产的权利称为( )
A．金融远期
B．金融期权
C．金融期货
D．金融互换
参考答案：B
People prefer ______ TV or listen to music rather than ______ newspapers to relax themselves. [ ]
A. watching; read
B. watching; to read
C. to watch; read
D. to watch; reading
在弹性限度内某弹簧下端悬挂500N重物时，总长为22cm，悬挂750N重物时，总长为23cm，该弹簧劲度系数为[ ]
A．2.5×104N/m
B．7.5×104N/m
C．5×104N/m
D．1.25×105N/m
