Figure: Gas-volume curves for two reaction conditions

The figure compares two gas-volume curves. Curve P reaches the same plateau sooner than Q. Which conclusion is justified?
P produces a different gas from the one Q produces
P uses a greater amount of the limiting reactant
Q has the larger initial rate of gas production
P has a faster rate but the same total gas yield
127 exam-style questions on Edexcel GCSE Chemistry 8.1 Rates of reaction, covering 8.1.1 Measuring and interpreting rates of reaction, 8.1.2 Collision theory and the factors affecting rate, and 8.1.3 Catalysts and enzymes. Each one has a worked solution and a mark scheme showing where the marks go.