如果x=2是一元二次方程x2-x+m=0的解,那么m的值是( )
A:0
B:2
C:6
D:-2
下列说法不正确的是( )
— Please say something about Zheng He.
— Oh! He is the Ming dynasty explorer of ______ all the Chinese are proud.
2H2(g)+CO(g)⇌CH3OH(g)△H=﹣90.0kJ•mol﹣1①
2CH3OH(g)⇌CH3OCH3(g)+H2O(g)△H=﹣24.5kJ•mol﹣1②
CO(g)+H2O(g)⇌CO2(g)+H2(g)△H=﹣41.1kJ•mol﹣1③