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A tank contains 1200L of brine with 15kg of dissolved salt Pure water enters the tank at a rate of 14L/min. The solution is kept thoroughly mixed and drains from the tank at the same rate. How much salt is in the tank after one hour? . Let k be a constant. Find the solution of the following differential equation dL = 2 dt kL ln(t) with initial-value L(1) = 1