(-0.25)^2005×(-4)^2004= (-0.25)×(-0.25)^2004×(-4)^2004= (-0.25)×[(-0.25)^2004×(-4)^2004]= (-0.25)×[(-0.25)×(-4)]^2004= (-0.25)×1^2004= -0.25×1= -0.25
-0.25
