Answer question numbers 4(a) – 4(d) on the basis of your understanding of the following paragraph and the related studied concepts:

India today is facing the problem of overuse of resources, contamination of water and soil and lack of methods of processing the waste. The time has come for the world to say goodbye to "single-use plastics". Steps must be undertaken to develop environment-friendly substitutes, effective plastic waste collection and methods of its disposal.

Indore treated 15 lakh metric tonnes of waste in just 3 years, through biomining and bioremediation techniques. Bioremediation involves introducing microbes into a landfill to naturally 'break' it down and biomining involves using trommel machines to sift through the waste to separate the 'soil' and the waste component. The city managed to chip away 15 lakh metric tonnes of waste at a cost of around ₹ 10 crore. A similar experiment was successfully carried out in Ahmedabad also.

4(a) State two methods of effective plastic waste collection in your school.

4(b) Name any two uses of "single-use plastic" in daily life.

4(c) If we discontinue the use of plastic, how can an environment-friendly substitute be provided?

4(d) Do you think microbes will work similarly in landfill sites as they work in the laboratory? Justify your answer.

4(a) Two methods of effective plastic waste collection in school are:

1. Segregation at Source: Placing separate, clearly labeled dustbins for dry/recyclable plastic waste and wet/biodegradable kitchen and garden waste across the school premises.
2. Collection Drives: Organizing student-led campaigns or establishing a dedicated recycling club where students can bring clean, dry plastic waste from home and school to be sent directly to recycling units.

4(b) Two uses of "single-use plastic" in daily life are:

1. Disposable plastic cups, glasses, and plates used for serving beverages and food at social gatherings or in trains.
2. Thin plastic carry bags and packaging wrappers for ready-made food items, chips, and biscuits.

4(c) Environment-friendly substitutes can be provided by:

1. Carrying reusable cloth-bags or jute-bags to put purchases in while shopping instead of using plastic carry bags.
2. Using disposable paper-cups instead of disposable plastic cups for serving beverages.

4(d) No, microbes will not work similarly in landfill sites as they do in a controlled laboratory environment. In a laboratory, environmental conditions such as temperature, moisture, pH, and oxygen availability are optimized for maximum microbial activity. In contrast, landfill sites have highly variable, uncontrolled ambient conditions, high compaction (which creates anaerobic pockets), and toxic chemical contaminants that can inhibit microbial growth and significantly slow down the rate of decomposition.