With reference to the planet Earth, consider the following statements:

    1. Rain forests produce more oxygen than that produced by oceans.
    2. Marine phytoplankton and photo-synthetic bacteria produce about 50% of world's oxygen.
    3. Well-oxygenated surface water contains several folds higher oxygen than that in atmospheric air.

Which of the statements given above is/are correct?


A bag contains 15 red balls and 20 black balls. Each ball is numbered either 1or 2 or 3. 20% of the red balls are numbered 1 and 40% of them are numbered 3. Similarly, among the black balls, 45% are numbered 2 and 30% are numbered 3. A boy picks a ball at random. He wins if the ball is red and numbered 3 or if it is black and numbered 1 or 2. What are the chances of his winning?


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