In the graph to the right it shows the activation energy needed in a reaction. assuming that both lines a and b are of the same reaction which line likely had an enzyme present? how do you know?

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.