1. (a) (i) Three ways of conserving energy in the home: 1. Switching off lights and appliances when not in use 2. Using energy-efficient appliances (e.g., LED bulbs) 3. Using natural light and ventilation (ii) Calculate the energy used: Energy = Power × Time = 4000 W × 12 h = 4000 × 3600 × 12 (convert hours to seconds) = 4000 × 43200 = 172,800,000 J or 172.8 MJ --- 2. (b) (i) Two examples of acid-base indicators: 1. Litmus 2. Methyl orange (ii) Colour change in orange juice (acidic): - Litmus: Blue → Red - Methyl orange: Orange → Red --- 3. (c) (i) Four activities to ensure a green economy in Ghana:* 1. Recycling and waste management 2. Promoting renewable energy use 3. Practicing sustainable farming 4. Environmental education and awareness (ii) Two primary greenhouse gases: 1. Carbon dioxide (CO₂) 2. Methane (CH₄)