Two types of leaf decompose for 20 days under the same conditions. The table shows their dry masses.
Table
| Leaf type | Initial dry mass / g | Final dry mass / g |
|---|---|---|
| P | 100 | 70 |
| Q | 80 | 40 |
Which statement correctly compares their percentage losses in dry mass?
P loses 30%30\%30% and Q loses 50%50\%50%.
P loses 70%70\%70% and Q loses 50%50\%50%.
P loses 70%70\%70% and Q loses 40%40\%40%.
P loses 30%30\%30% and Q loses 40%40\%40%.
44 exam-style questions on Edexcel GCSE Biology 9.3 Material cycles and decomposition, covering 9.3.1 Cycling of materials through ecosystems, 9.3.2 The carbon cycle, 9.3.3 The water cycle, 9.3.4 The nitrogen cycle, 9.3.5 Indicator species and pollution, 9.3.6 Decomposition in preservation and composting, and 9.3.7 Rate changes in decay of biological material. Each one has a worked solution and a mark scheme showing where the marks go.