Assignment:
A tank initially contains 100 gallons of a solution that holds 10 pounds of a chemical. A solution containing 1 pound of the chemical runs into the tank at a rate of 4 gallons per minute, and the well-mixed mixture runs out of the tank at a rate of 6 gallons per minute.
a. How much chemical is in the tank after 25 minutes?
b. How much chemical is in the tank after 50 minutes?
Provide complete and step by step solution for the question and show calculations and use formulas.