442. It is difficult to bon potatoes at the top or a mountain because
   (a) the water available is hard
   (b) it is colder than at sea level
   (c) the potatoes become hard
   (d) the boiling point of water is lower at that height on account of low
       atmospheric pressure
Ans: (d)
443. If a body is taken from the earth to the moon
   (a) both its mass and weight will be different
   (b) its mass will be different but the weight will remain the same
   (c) its mass and weight will both remain unchanged
   (d) its mass will remain the same but weight will be different
Ans: (d)
444. The instrument used to measure the strength of electric current at a point
   is
   (a) Ammeter
   (b) Altimeter
   (c) Adrinometer
   (d) Anemometer
Ans: (a)
445. One finds it more difficult to walk on ice than on a concrete road because
   (a) there is more friction on ice than on concrete surface
   (b) ice is soft and spongy while concrete is hard
   (c) the friction between ice and the feet is less than that between the concrete
       and the feet
   (d) None of them
Ans: (c)
446. An electric kettle used for boiling hard water has a white scale deposited
   on its heating element. This consists or
   (a) sugar
   (b) sodium carbonate
   (c) common salt
   (d) carbonates of calcium and magnesium
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