透平第一临界转速为()rpm。
A.5000-6000
B.4500-6500
C.6180
D.2950
参考答案:D
亚洲西部主要分布的人种是[ ]
A、白色人种
B、黑色人种
C、黄色人种
D、白色与黑色人种混居
It’s said that there _____ a football match on TV this evening.
A.will have
B.is going to be
C.has
D.is going to have