如果市场收益为5%与25%的可能性相同，两只股票的期望收益率为( )。

A．12.5%；7%

B．18%；9%

C．12.5%；9%

D．18%；10%

Last week the staff made______ suggestions, but unluckily they were just ______ impractical by the manager.

A．dozen of; dismissed for

B．many dozens of; dismissed from

C．two dozen; being dismissed as

D．dozens of; dismissed as