A:x≥0
B:x≠±5
C:x≥0且x≠5
D:x>0且x≠5
软流层位于()
观察下图,1975—1982(X轴以下部分)年美国经济的状况,出现的直接原因是( )
____ He's my brother.
____ Who's that boy?
____ Yes, she is.
____ Is she your mother?
____ No, he isn't. He's my teacher.
____ Is he your father?