Many physical processes are exponential in nature. a typical way of cleaning a tank of contaminated water is to run in clean water at a constant rate, stir, and let the mixture run out at the same rate. suppose there are initially 100 pounds of a contaminant in a large tank of water. assume that the cleaning method described above removes 20% of the remaining contaminant each hour. round your answer to one decimal place. how much contaminant is removed from the tenth (t = 10) to the thirteenth (t = 13) hour of the cleaning process? lb