The table shows the dry mass of leaves during decomposition.
Table
| Time / days | Dry mass / g |
|---|---|
| 0 | 120 |
| 10 | 90 |
| 20 | 70 |
| 30 | 60 |
What is the mean rate of dry mass loss between day 10 and day 30?
1.0 g day−11.0\,\text{g day}^{-1}1.0g day−1
2.0 g day−12.0\,\text{g day}^{-1}2.0g day−1
3.0 g day−13.0\,\text{g day}^{-1}3.0g day−1
1.5 g day−11.5\,\text{g day}^{-1}1.5g day−1
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.