1. Consider the following statements with reference to salt weathering:

  1. Salts in rocks expand due to thermal action, hydration and crystallization.
  2. Salts like calcium, sodium, magnesium and barium have a tendency to expand.
  3. Salt weathering is a typical example of chemical weathering.

Which of the statements given above is/are correct?


1. A distribution consists of 3 components with frequencies 45, 40 and 55 having their means 2, 2.5 and 2 respectively. What is the mean of the combined distribution?

     


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