____ ____ ____ play badminton.
函数f(x)=lgx+1-2x的定义域为( )
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已知下列热化学方程式:2H2(g)+O2(g)===2H2O(g) △H=-483.6 kJ·mol-1 H2(g)+12O2(g)===2H2O(g)△H=-241.8 2H2(g)+O2(g)===2H2O(g) △H=-571.6 则氢气的燃烧热是( )