171: Why are dewdrops not formed on a cloudy night?
(a) Clouds absorb the radiation released from the Earths surface.
(b) Clouds reflect back the Earths radiation.
(c) The Earths surface would have low temperature on cloudy nights.
(d) Clouds deflect the blowing wind to ground level.
172: The fundamental objective of Panchayati Raj system is to ensure which among the following?
1. People's participation in development
2. Political accountability
3. Democratic decentralization
4. Financial mobilization
Select the correct answer using the code given below.
(a) 1, 2 and 3 only
(b) 2 and 4 only
(c) 1 and 3 only
(d) 1, 2, 3 and 4
173: 'Net metering' is sometimes seen in the news in the context of promoting the
(a) production and use of solar energy by the households/consumers
(b) use of piped natural gas in the kitchens of households
(c) installation of CNG kits in motor-cars
(d) installation of water meters in urban households
174: A merchant wants a gross profit of 25 per cent on the sales. Thus the percentage he should add to the cost price will be:
(a) 25 per cent
(b) 33 per cent
(c) 66 per cent
(d) 75 per cent
175: There is some concern regarding the nanoparticles of some chemical elements that are used by the industry in the manufacture of various products. Why?
1. They can accumulate in the environment, and contaminate water and soil.
2. They can enter the food chains.
3. They can trigger the production of free radicals.
Select the correct answer using the code given below.
(a) 1 and 2 only
(b) 3 only
(c) 1 and 3 only
(d) 1, 2 and 3