641: With reference to the Indian freedom struggle, which one of the following statements is not correct?
(a) Hakim Ajmal Khan was one of the leaders to start a nations list and militant Ahrar movement
(b) When the Indian National Congress was formed, Sayyid Ahmad Khan opposed it
(c) The All-India Muslim League which was formed in 1906 vehemently opposed the partition of Bengal and separate electorates
(d) Maulana Barkaullah and Maulana Obeidullah Sindhi were among those who formed a Provisional Government of India in Kabul
642: There are two identical red, two identical black and two identical white balls. In how many different ways can the balls be placed in the cells (each cell to contain one ball) shown below such that balls of the same colour do not occupy any two consecutive cells?
(a) 15
(b) 18
(c) 24
(d) 30
643: Consider the following statements regarding bones in the human body :
1. They consist of 80% solid matter and 20% water.
2. Solid matter in the bones is made mainly of cartilage.
3. Impregnation of salts including carbonates and phosphates of lime imparts hardness to the bones.
4. In old age, the proportion of lime decreases and bones become brittle and break easily.
Of these statements :
(a) 1, 2 and 3 are correct
(b) 2 and 4 are correct
(c) 2 and 3 are correct
(d) 1, 2, 3 and 4 are correct
644: The sun derives its energy from:
(a) Nuclear fission reactions.
(b) Nuclear fusion reactions.
(c) Oxidation of helium.
(d) Fission of noble metals.
645: The stones formed in human kidney consist mostly of
(a) calcium oxalate
(b) sodium acetate
(c) magnesium sulphate
(d) calcium