A tank originally contains 320 gal of fresh water Then water

A tank originally contains 320 gal of fresh water. Then water containing 1/2 of salt per gal is poured into the tank at a rate of 4 gal/min, and the mixture is allowed to leave at the same rate. After 10 minutes the salt water solution flowing into the tank suddenly switches to fresh water flowing in at a rate of 4 gal/min while the solution continues to leave the tank at the same rate. Find the Laplace transform of the amount of salt y (t) In the tank.

Solution

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