测定()煤样可采用粒度小于13mm或小于6mm的样品,其样品的质量应当不小于3kg或1.25kg。
A、全水分
B、灰分
C、挥发分
D、全硫分
参考答案:A
Your sister had a bad cold, ______ she? [ ]
A. wasn't
B. doesn't
C. hadn't
D. didn't
下列装置合理,且能达到实验目的的是