2051: With reference to 'fly ash' produced by the power plants using coal as fuel, which of the following statements is/are correct?
1. Fly ash can be used in the production of bricks for building construction.
2. Fly ash can be used as a replacement for some of the Portland cement concrete.
3. Fly ash is made up of silicon dioxide and calcium oxide only, and does not contain any toxic elements.
Select the correct answer using the code given below.
(a) 1 and 2
(b) 2 only
(c) 1 and 3
(d) 3 only
2052: Which one of the following pairs is correctly matched ?
(a) Harappan Civilisation : Painted Grey Ware
(b) The Kushans : Gandhara School of Art
(c) The Mughals : Ajanta Paintings
(d) The Marathas : Pahari School of Painting
2053: Among the following, which one lays eggs and does not produce young ones directly?
(a) Kangaroo
(b) Echidna
(c) Whale
(d) Porcupine
2054: Assertion (A) :
The frequency of floods in North Indian plains has increased during the last couple of decades.
Reason (R) :
There has been reduction in the depth of river valleys due to deposition of silt.
(a) Both A and R are true, and R is the correct explanation of A
(b) Both A and R are true, but R is not a correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
2055: The thermal power plant of Bokaro is located in
(a) Bihar
(b) Chhattisgarh
(c) Jharkhand
(d) Orissa