Concentration Changes Over Time Practice Test

Five concentration–time curves (Curves 1–5) show $B$ for the reaction $A \rightarrow B$ under different conditions. All begin at $B=0$ and level off when formation is complete. Which curve shows the greatest initial change in $B$ over a short initial time interval?

A student compares five concentration–time curves (Curves 1–5) for reactant $A$ in the reaction $A \rightarrow$ products. All trials start with the same initial $A$ and proceed until completion (each curve levels off). Which curve indicates the reaction that takes the longest time to reach completion?