焦油精制率要求大于()。
A.88.8%
B.90%
C.95%
D.98%
参考答案:D
published fifty years ago, his work still attracts much attention at present.
A.As
B.Though
C.Apart from
D.Despite
下面哪个角度不可能是赤纬角?()
A、-23
B、0
C、23
D、67