A.815℃,40min B.900℃,1h C.815℃,1h D.900℃,40min
A.無(wú)煙煤>褐煤>煙煤 B.煙煤>褐煤>無(wú)煙煤 C.褐煤>煙煤>無(wú)煙煤 D.無(wú)煙煤>煙煤>褐煤
A.△≈1S B.△≈2s C.△≈3s D.△≈4s