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5. Sketch the curve whose equation is y : 111(2331) for 3: > % The region bounded by this curve, the axes and the line 3; : 1113 is rotated completely about the Litaxis. Calculate the volume of solid generated. [8] 6. Newton's law of cooling states that the rate of cooling of an object is proportional to the difference in temperature between the object and its surroundings. If an object is kept in an environment whose temperature is kept constant at 15C and the object takes 20 minutes to cool from 95C to 55C, determine how many longer it will take for the object to cool down to 25C. [6] 7. Solve the dierential equation d y + ytanzr : sian, where 0