(c) 4          2        3          1
    (d) 2          4        1          3
Ans: (d)
73. Consider the following statements: In nuclear power reactors: [CDS 1999]
    1) Uranium-235 is used as the fission material.
    2) Graphite is used as a moderator.
    3) Rods of lead are used to control the rate of nuclear reaction.
    Which of the above statements are correct?
    (a)  1, 2 and 3
    (b)  1 and 2
    (c)  2 and 3
    (d)  1 and 3
Ans: (b)
74. Which one of the following is a mixture? [CDS 1999]
    (a) Lime
    (b) Table salt
    (c) Sugar
    (d) Sea water
Ans: (a)
75. Amalgam is a mixture of: [IAS 2003]
    (a) any non-metal and chlorine
    (b) any metal and florine
    (c) any non-metal and lead
    (d) any metal and mercury
Ans: (d)
76. Match the following: [CDS 1999]
    A. Sodium Palmitate     1. Ore
    B. Galena               2. Fertilizer
    C. NPK                  3. Soap
    D. Cellulose            4. Natural polymer
         A         B        C          D
    (a)  1         2        3          4
    (b)  3         1        2          4
    (c)  3         2        4          1
    (d)  4         1        3          2
Ans: (b)
77. Match the following: [CDS 1999]
    Theory                             Scientist
    A. Theory of Nuclear Fission       1. George Gamow
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