_____ global financial crisis of 2009 be
题型：选择题
问题：
_____ global financial crisis of 2009 became _____ concern for people all over the world．
A．The; the
B．The; a
C．不填；不填
D．A ； the
题型：选择题
_____ global financial crisis of 2009 became _____ concern for people all over the world．
A．The; the
B．The; a
C．不填；不填
D．A ； the
，且a∈[0，π]，则tanα=().
