-----I’m more than happy to go out this weekend.

----- ______. We’ve got so much work to do at that time.

A．Don't worry

B．Forget it

C．Don't say so

D．Don't mention it

煤中硫化铁硫和硫酸盐硫是（）硫。

A.可燃；

B.无机；

C.不可燃；

D.有机。