Leaf P grows from 4 cm² to 6 cm² in 2 days…

Step 1. Absolute rates. Leaf P gains $2\ \text{cm}^2$ in $2$ days, so $1\ \text{cm}^2$/day. Leaf Q gains $4\ \text{cm}^2$ in $2$ days, so $2\ \text{cm}^2$/day.

Step 2. Relative rates. Leaf P: $\dfrac{1}{4} \times 100 = 25\%$ per day. Leaf Q: $\dfrac{2}{40} \times 100 = 5\%$ per day.

Step 3. Compare. Leaf Q gains more area each day, so it has the higher absolute rate. Leaf P gains more for its size, so it has the higher relative rate.