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Lesson 13: Our Environment and Natural Resources, Multiple Choice Questions (MCQs). Tick (/) the correct answers: Page No. 132, , 1. (b) 2. (a) 3. (b), Multiple Choice Questions (MCQs). Tick (“) the correct answers: Page No. 133, 1. (a) 2. (b) 3. (c), EXERCISES, Section-A Page No. 135-136, , Class Response, A. Oral Questions:, 1. Addition of harmful substances in the environment is called pollution., 2. The resources that we get from the nature are called natural resources., 3. The heating of the earth’s atmosphere due to the trapping of heat, energy reflected from the earth’s surface by carbon dioxide and other, gases in the atmosphere is called greenhouse effect., B. Science Quiz:, 1. Air pollution, water pollution, soil pollution and noise pollution, 2. Carbon dioxide/Ozone/Methane/Nitrogen oxide/Water vapour, 3. Fertile topsoil, minerals, coal and petroleum, Worksheet, A. Multiple Choice Questions (MCQs):, 1. (c) 2. (b) 3. (c) 4. (b), B. Fill in the blanks:, , 1. water, 2. Carbon dioxide, 3. sewage, Section-B Page No. 136-37, , A. Multiple Choice Questions (MCQs) Scientific/Practical skills:, 1. (a) 2. (c), , qa,, , B. Very short answer questions:, , 1. CNG is a cleaner fuel., , 2. It causes global warming., , C. Short answer questions:, , 1. The heating of the earth’s atmosphere due to the trapping of heat, energy reflected from the earth’s surface by greenhouse gases in the, atmosphere is called greenhouse effect., , 2. The resources which either never get exhausted or are replaced naturally, within a reasonable time period are renewable resources. E.g., sunlight,, water, wind and forest. The resources which cannot be replaced within a, reasonable time period, if used up are called non-renewable resources., E.g., coal, petroleum, minerals and topsoil, , 3. (a) Rohan prefers to go to nearby places by a bicycle instead of a car to, , save fuel and also to reduce the level of air pollution., (b) Yes, Rohan’s act is environment friendly. From Rohan, we can learn, to be environment friendly in all our actions., D. Long answer questions:, , 1. Human activities like burning of fossil fuels by automobiles and, industries, and cutting and burning of forests release a lot of carbon, dioxide and many other harmful gases. These are responsible for, increasing greenhouse effect., , 2. The resources that we get from the nature are called natural resources., Different ways for conservation of natural resources are as follows:, , (i) We should plant more and more trees so that forest cover does not, decrease., (ii) Catalytic convertors should be installed in vehicles., (iii) We should prevent water pollution to keep our rivers clean., (iv) We should use renewable sources of energy like solar energy, wind, energy and hydroenergy to conserve the fossil fuels., (v) Rainwater harvesting should be adopted., (vi) Minerals can be conserved by reusing them again by recycling., E.g., glass bottles, metallic cans can be recycled., E. Think and answer:, 1. We cut trees for making paper. When we use paper again and again by, , rarucling it wa chall ha ahla ta crancarve faractc