Study the map of Taita Hills 1:50,000 (sheet 189/4) and answer the following questions.

(a) The four-figure grid reference of Rigga Hill is 3870. (b) Step 1: Measure the length of road AB on the map. Length on map = 28 cm. Step 2: Determine the representative fraction (RF) of the map. RF = 1 : 50000. Step 3: Convert map length to ground distance in km. 1\ cm (map) = (50000)/(100000)\ km (ground) = 0.5\ km. Ground length = map length × 0.5\ km/cm. Step 4: Substitute the measured length. 28\ cm × 0.5\ kmcm = 14\ km. The length of road AB is 14\ km. (c) The area experiences a modified equatorial climate. Evidence: High altitude (over 1500m e.g. Rigga Hill). Cool temperatures. Forest vegetation on hilltops. High rainfall. Perennial rivers e.g. Voi River. Reliable rainfall. Dense nucleated settlements on hilltops. Fertile volcanic soils and adequate rainfall. Tea and coffee growing areas. Cool moist conditions. (d)(i) Causes of migration from the area (citing map evidence): 1. Steep slopes/relief (mountainous terrain around grid square 3870). Difficult for farming/mechanisation. People migrate to lowlands. 2. Congestion/overpopulation (dense settlements e.g. Wundanyi, dense housing). Limited land pushes people out. 3. Poor transport (few roads, winding e.g. A to B road). Limits market access, encourages out-migration. 4. Limited economic opportunities (few industries, subsistence farming shown). Youth migrate to urban centres like Mombasa. (d)(ii) Factors influencing agricultural activities (citing map evidence): 1. Relief: Steep slopes (Taita hills) limit large-scale farming; terracing used. 2. Climate: High rainfall (forests, perennial rivers) favours crops like tea/banana. 3. Soils: Fertile volcanic (hilltop farms, dense population). Supports cash crops. 4. Drainage: Poor in valleys (swamps) limits cultivation there. (e) Two rocks of volcanic origin: 1. Basalt 2. Pumice Basalt, Pumice (f)(i) Mechanical formation of soil: Physical weathering breaks down pre-existing rocks into smaller particles without chemical change. Temperature changes cause exfoliation (expansion/contraction). Frost action: Water freezes in cracks, expands, splits rocks (in highlands). Action of wind-blown sand grinds rocks (abrasion). Results in angular fragments forming soil. (g)(i) Three problems during data collection on rocks in local environment: 1. Difficult terrain (steep slopes, thick vegetation). Hard to access sites. 2. Weather (heavy rains). Makes fieldwork hazardous/slippery. 3. Limited tools (no advanced equipment for sampling). Rely on observation. (g)(ii) Two economic uses of rocks likely to identify: 1. Building stones (quarries shown on map). 2. Ballast for roads (crushed rock along roads). (h)(i) Two types of weathering: 1. Physical/mechanical weathering. 2. Chemical weathering. (h)(ii) Two ways through which the strength of an earthquake is measured: 1. Richter scale: Measures magnitude/amplitude of seismic waves using logarithm. E.g. 5.0 is 10x stronger than 4.0. Records energy released at source. 2. Modified Mercalli Intensity (MMI) scale: Measures effects/intensity on surface (I-XII). E.g. VIII causes damage to buildings. Subjective based on observations.