(ii) Briefly describe helicoidal flow. [3] (a) (i) Define the terms velocity and discharge as they apply to river channels. [4] (ii) Briefly describe helicoidal flow. [3] (b) With the use of diagrams, describe and explain the formation of: (i) waterfalls; (ii) gorges. [8] (c) To what extent can human activities affect river channels? [10]  

(a) (i) Define the terms velocity and discharge as they apply to river channels. [4] (ii) Briefly describe helicoidal flow.[3] (b) With the use of diagrams, describe and explain the formation of: (i) waterfalls; (ii) gorges. [8] (c) To what extent can human activities affect river channels? [10]

For one agricultural system (arable or pastoral) which you have studied, (a) (i) name the system and locate your chosen example(s), (ii) describe how physical factors affect agricultural land-use and practices in this system. [10] (b) To what extent are recent changes to the system chosen in (a) the result of political factors? [15]

For one agricultural system (arable or pastoral) which you have studied, (a) (i) name the system and locate your chosen example(s), (ii) describe how physical factors affect agricultural land-use and practices in this system. [10] (b) To what extent are recent changes to the system chosen in (a) the result of political factors? [15]