428. Sun spots are
   (a) the mountains found on the surface of the Sun
   (b) the dark patches on the sun having less temperature than the normal sun"s
       surface
   (c) ionized gas found near the solar surface
   (d) the magnetic storms on the surface of the Sun
Ans: (b)
429. Match the following:
   Column-I               Column-II
   A. Shooting Star       1. Comet
   B. Titan               2. Meteor
   C. Saturn              3. Satellite
   D. Halley"s Comet      4. Planet
       A      B     C     D
   (a) 3      2     4     1
   (b) 2      4     1     3
   (c) 2      3     4     1
   (d) 2      3     1     4
Ans: (c)
430. Who first established the fact that the earth revolves round the sun?
   (a) Sir Isaac Newton
   (b) Kepler
   (c) Copernicus
   (d) Ptolemy
Ans: (c)
431. Lightning conductors are made of
   (a) iron
   (b) chromium
   (c) copper
   (d) steel
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