1. Volcanoes hotspring waterfall

4. Types of plate boundaries - Constructive plate boundaries - Destructive plate boundaries - Conservative plate boundaries

5. Types of plate boundary: destructive plate boundary

6. Sulphuric gases -----> poison people -----> acid rain Lava---------------------> burns things--- Carbon dioxide------> greenhouse effect Volcanic ash----------> mudflows-------

8. Geothermal power Metals and Minerals Fertile soil---------------- Tourist attraction

16. When the river water is unable to remove the resistant rock layer but is enough to erode the soft rock downstream, the river falls down vertically in the form of a waterfall.

17. Middle course Lower course

19. Block: Water descends from a relatively wide stream or river. Cascade: Water descends a series of rock steps. Cataract: A large, powerful waterfall. Chute: A large quantity of water forced through a narrow, vertical passage. Fan: Water spreads horizontally as it descends while remaining in contact with bedrock. Frozen: Any waterfall which has some element of ice. Horsetail: Descending water maintains some contact with bedrock. Plunge: Water descends vertically, losing contact with the bedrock surface. Punchbowl: Water descends in a constricted form and then spreads out in a wider pool. Segmented: Distinctly separate flows of water form as it descends. Tiered: Water drops in a series of distinct steps or falls. Multi-step: A series of waterfalls one after another of roughly the same size each with its own sunken plunge pool

21. The falling water at the waterfall produces strong hydraulic action, forming a circular pool of water at the base of the waterfall called a plunge pool.