Which type of engine is the most environmentally friendly and
why?

Why is it that 85.48 rounded to two significant figures is 85 and not 86?

Compounds a and b react to form compounds c and d according to the equation: aa + bb → cc + dd. under which conditions will the rate law be given by the equation: rate = k[a]a[b]b? a. the reaction takes place in one step. b. the reaction is endothermic. c. the reaction is exothermic. d. the reaction involves more than one step.

Amodel of an atom is shown below. which element is represented by this model of an atom? boron, carbon, neon, or sodium?