3826: Sodium vapour lamps are preferred to incandescent lamps because of:
(a) Higher efficiency
(b) Higher tolerance in voltage fluctuations
(c) Easy installation
(d) Higher intensity of illumination
3827: Due to some reasons, if there is a huge fall in the population of species of butterflies, what could be its likely consequence/consequences?
1. Pollination of some plants could be adversely affected.
2. There could be a drastic increase in the fungal infections of some cultivated plants.
3. It could lead to a fall in the population of some species of wasps, spiders and birds.
Select the correct answer using the code given below:
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
3828: Different seasons are formed because:
(a) Sun is moving around the earth
(b) Of revolution of the earth around the sun on its orbit
(c) Of rotation of the earth around its axis
(d) All of the above
3829: Roman settlement in India is found at
(a) Ujjain
(b) Kshudrakas
(c) Arikmedu
(d) Koshambi
3830: Which of the following Five-Year Plans was terminated one year before its completion?
(a) Second
(b) Third
(c) Fourth
(d) Fifth