电厂用煤灰熔点软化温度一般要求大于()℃。
A.1250
B.1150
C.1200
参考答案:A
已知某原子中共有82个粒子,其中有30个粒子不带电,则该原子的核电荷数是______,相对原子质量是______.
I find it astonishing that she _____ treat you like this in public.
A.should
B.must
C.may
D.would