What distinguishes 'onstem' reservoirs from 'offstem' reservoirs?
- Onstem reservoirs are located in upland areas and formed by damming rivers, while offstem reservoirs are in lowlands and use pumped water.
- Onstem reservoirs rely on pumping water, whereas offstem reservoirs are naturally formed.
- There is no significant difference between onstem and offstem reservoirs.
A2, 3
BAll
C1, 3
D1 only