电子捕获检测器对含有S、P元素的化合物具有很高的灵敏度。( )
参考答案:错
There are many holidays in China. Which holiday is in May? [ ]
A. National Day
B. Spring Festival
C. Labour Day
D. Teachers' Day
在半通行地沟内,管道或保温层外表面至沟顶的净距取值范围为( )mm。
A.200~300 B.200~250 C.150~200 D.100~150