4. Using either the original differential equation from part 2, or the solution from part 3, find the equilibrium mass of heparin in the patient's body, reached after a long period of treatment. 5. Consider a patient whose treatment with heparin is being halted, so that only metabolism is affecting their heparin levels . The patient currently has a level of 12 mg of heparin in their system, and a level of 0.5 mg is the lowest still considered to be clinically effective. How long does it take after the drug supply is stopped for his or her heparin level to drop below the clinically effective threshold